You are viewing a plain text version of this content. The canonical link for it is here.
Posted to commits@logging.apache.org by rp...@apache.org on 2021/12/22 02:43:50 UTC
[logging-log4j-site] branch asf-staging updated: Update 2.17.0 About page and Security page for releases 2.3.1 and 2.12.3
This is an automated email from the ASF dual-hosted git repository.
rpopma pushed a commit to branch asf-staging
in repository https://gitbox.apache.org/repos/asf/logging-log4j-site.git
The following commit(s) were added to refs/heads/asf-staging by this push:
new 550ac0a Update 2.17.0 About page and Security page for releases 2.3.1 and 2.12.3
550ac0a is described below
commit 550ac0ad501b857267c129fc934412c013599b84
Author: Remko Popma <re...@yahoo.com>
AuthorDate: Wed Dec 22 11:43:41 2021 +0900
Update 2.17.0 About page and Security page for releases 2.3.1 and 2.12.3
---
log4j-2.17.0/index.html | 72 +++----
log4j-2.17.0/security.html | 528 +++++++++++++++++++++++----------------------
2 files changed, 299 insertions(+), 301 deletions(-)
diff --git a/log4j-2.17.0/index.html b/log4j-2.17.0/index.html
index 3ea2298..85e1446 100644
--- a/log4j-2.17.0/index.html
+++ b/log4j-2.17.0/index.html
@@ -157,47 +157,39 @@
limitations under the License.
-->
<h1>Apache Log4j 2</h1>
-<p>Apache Log4j 2 is an upgrade to Log4j that provides significant improvements over its predecessor, Log4j 1.x, and provides many of the improvements available in Logback while fixing some inherent problems in Logback’s architecture.</p>
-<p><a name="CVE-2021-45105"></a></p><section>
-<h2><a name="Important:_Security_Vulnerability_CVE-2021-45105"></a>Important: Security Vulnerability CVE-2021-45105</h2>
-<p>The Log4j team has been made aware of a security vulnerability, CVE-2021-45105, that has been addressed in Log4j 2.17.0 for Java 8 and up.</p>
-<p>Summary: Apache Log4j2 does not always protect from infinite recursion in lookup evaluation.</p><section><section>
-<h4><a name="Details"></a>Details</h4>
-<p>Apache Log4j2 versions 2.0-alpha1 through 2.16.0 did not protect from uncontrolled recursion from self-referential lookups. When the logging configuration uses a non-default Pattern Layout with a Context Lookup (for example, $${ctx:loginId}), attackers with control over Thread Context Map (MDC) input data can craft malicious input data that contains a recursive lookup, resulting in a StackOverflowError that will terminate the process. This is also known as a DOS (Denial of Service) at [...]
-<h4><a name="Mitigation"></a>Mitigation</h4>
-<p>From version 2.17.0 (for Java 8), only lookup strings in configuration are expanded recursively; in any other usage, only the top-level lookup is resolved, and any nested lookups are not resolved.</p>
-<p>In prior releases this issue can be mitigated by ensuring your logging configuration does the following:</p>
-<ul>
+<p>Apache Log4j 2 is an upgrade to Log4j that provides significant improvements over its predecessor, Log4j 1.x, and provides many of the improvements available in Logback while fixing some inherent problems in Logback’s architecture.</p><section>
+
+
+ <h2><a name="Important:_Security_Vulnerabilities_CVE-2021-45105.2C_CVE-2021-45046_and_CVE-2021-44228"></a>Important: Security Vulnerabilities CVE-2021-45105, CVE-2021-45046 and CVE-2021-44228</h2>
+ <p><a name="CVE-2021-45105"></a></p><section>
+ <h3><a name="CVE-2021-45105"></a>CVE-2021-45105</h3>
+ <p>Summary: Apache Log4j2 does not always protect from infinite recursion in lookup evaluation.</p><section>
+ <h4><a name="Details"></a>Details</h4>
+ <p>Apache Log4j2 versions 2.0-alpha1 through 2.16.0 did not protect from uncontrolled recursion from self-referential lookups. When the logging configuration uses a non-default Pattern Layout with a Context Lookup (for example, $${ctx:loginId}), attackers with control over Thread Context Map (MDC) input data can craft malicious input data that contains a recursive lookup, resulting in a StackOverflowError that will terminate the process. This is also known as a DOS (Denial of [...]
+ <h4><a name="Mitigation"></a>Mitigation</h4>
+ <p>Upgrade to Log4j 2.3.1 (for Java 6), 2.12.3 (for Java 7), or 2.17.0 (for Java 8 and later).</p></section><section>
+ <h4><a name="Reference"></a>Reference</h4>
+ <p>Please refer to the <a class="externalLink" href="https://logging.apache.org/log4j/2.x/security.html#CVE-2021-45105">Security page</a> for details and mitigation measures for older versions of Log4j.</p>
+ <p><a name="CVE-2021-45046"></a></p></section></section><section>
+ <h3><a name="CVE-2021-45046"></a>CVE-2021-45046</h3>
+ <p>Summary: Apache Log4j2 Thread Context Lookup Pattern vulnerable to remote code execution in certain non-default configurations.</p><section>
+ <h4><a name="Details"></a>Details</h4>
+ <p>It was found that the fix to address CVE-2021-44228 in Apache Log4j 2.15.0 was incomplete in certain non-default configurations. When the logging configuration uses a non-default Pattern Layout with a Context Lookup (for example, $${ctx:loginId}), attackers with control over Thread Context Map (MDC) input data can craft malicious input data using a JNDI Lookup pattern, resulting in an information leak and remote code execution in some environments and local code execution [...]
+ <h4><a name="Mitigation"></a>Mitigation</h4>
+ <p>Upgrade to Log4j 2.3.1 (for Java 6), 2.12.3 (for Java 7), or 2.17.0 (for Java 8 and later).</p></section><section>
+ <h4><a name="Reference"></a>Reference</h4>
+ <p>Please refer to the <a class="externalLink" href="https://logging.apache.org/log4j/2.x/security.html#CVE-2021-45046">Security page</a> for details and mitigation measures for older versions of Log4j.</p>
+ <p><a name="CVE-2021-44228"></a></p></section></section><section>
+ <h3><a name="CVE-2021-44228"></a>CVE-2021-44228</h3>
+ <p>Summary: Log4j’s JNDI support has not restricted what names could be resolved. Some protocols are unsafe or can allow remote code execution.</p><section>
+ <h4><a name="Details"></a>Details</h4>
+ <p>One vector that allowed exposure to this vulnerability was Log4j’s allowance of Lookups to appear in log messages. This meant that when user input is logged, and that user input contained a JNDI Lookup pointing to a malicious server, then Log4j would resolve that JNDI Lookup, connect to that server, and potentially download serialized Java code from that remote server. This in turn could execute any code during deserialization. This is known as a RCE (Remote Code Ex [...]
+ <h4><a name="Mitigation"></a>Mitigation</h4>
+ <p>Upgrade to Log4j 2.3.1 (for Java 6), 2.12.3 (for Java 7), or 2.17.0 (for Java 8 and later).</p></section><section>
+ <h4><a name="Reference"></a>Reference</h4>
+ <p>Please refer to the <a class="externalLink" href="https://logging.apache.org/log4j/2.x/security.html#CVE-2021-44228">Security page</a> for details and mitigation measures for older versions of Log4j.</p></section></section></section><section>
+
-<li>In PatternLayout in the logging configuration, replace Context Lookups like ${ctx:loginId}or $${ctx:loginId} with Thread Context Map patterns (%X, %mdc, or %MDC).</li>
-<li>Otherwise, in the configuration, remove references to Context Lookups like ${ctx:loginId} or $${ctx:loginId} where they originate from sources external to the application such as HTTP headers or user input.</li>
-</ul></section><section>
-<h4><a name="Reference"></a>Reference</h4>
-<p>Please refer to the <a href="security.html#CVE-2021-45105">Security page</a> for details and mitigation measures for older versions of Log4j.</p>
-<p><a name="CVE-2021-45046"></a></p></section></section></section><section>
-<h2><a name="Important:_Security_Vulnerability_CVE-2021-45046"></a>Important: Security Vulnerability CVE-2021-45046</h2>
-<p>The Log4j team has been made aware of a security vulnerability, CVE-2021-45046, that has been addressed in Log4j 2.12.2 for Java 7 and 2.16.0 for Java 8 and up.</p>
-<p>Summary: Apache Log4j2 Thread Context Lookup Pattern vulnerable to remote code execution in certain non-default configurations.</p><section><section>
-<h4><a name="Details"></a>Details</h4>
-<p>It was found that the fix to address CVE-2021-44228 in Apache Log4j 2.15.0 was incomplete in certain non-default configurations. When the logging configuration uses a non-default Pattern Layout with a Context Lookup (for example, $${ctx:loginId}), attackers with control over Thread Context Map (MDC) input data can craft malicious input data using a JNDI Lookup pattern, resulting in an information leak and remote code execution in some environments and local code execution in all envir [...]
-<p>Note that previous mitigations involving configuration such as setting the system property log4j2.formatMsgNoLookups to true do NOT mitigate this specific vulnerability.</p></section><section>
-<h4><a name="Mitigation"></a>Mitigation</h4>
-<p>In version 2.12.2 (for Java 7), Log4j disables access to JNDI by default. Usage of JNDI in configuration now needs to be enabled explicitly. Calls to the JndiLookup will now return a constant string. Also, Log4j now limits the protocols by default to only java. The message lookups feature has been completely removed. Lookups in configuration still work.</p>
-<p>From version 2.16.0 (for Java 8), the message lookups feature has been completely removed. Lookups in configuration still work. Furthermore, Log4j now disables access to JNDI by default. Users are advised not to enable JNDI in Log4j 2.16.0. If the JMS Appender is required, use Log4j 2.12.2.</p></section><section>
-<h4><a name="Reference"></a>Reference</h4>
-<p>Please refer to the <a href="security.html#CVE-2021-45046">Security page</a> for details and mitigation measures for older versions of Log4j.</p>
-<p><a name="CVE-2021-44228"></a></p></section></section></section><section>
-<h2><a name="Important:_Security_Vulnerability_CVE-2021-44228"></a>Important: Security Vulnerability CVE-2021-44228</h2>
-<p>The Log4j team has been made aware of a security vulnerability, CVE-2021-44228, that has been addressed in Log4j 2.12.2 and Log4j 2.16.0.</p><section><section>
-<h4><a name="Summary"></a>Summary</h4>
-<p>Log4j’s JNDI support has not restricted what names could be resolved. Some protocols are unsafe or can allow remote code execution.</p></section><section>
-<h4><a name="Details"></a>Details</h4>
-<p>One vector that allowed exposure to this vulnerability was Log4j’s allowance of Lookups to appear in log messages. This meant that when user input is logged, and that user input contained a JNDI Lookup pointing to a malicious server, then Log4j would resolve that JNDI Lookup, connect to that server, and potentially download serialized Java code from that remote server. This in turn could execute any code during deserialization. This is known as a RCE (Remote Code Execution) att [...]
-<h4><a name="Mitigation"></a>Mitigation</h4>
-<p>In version 2.12.2 (for Java 7), Log4j disables access to JNDI by default. Usage of JNDI in configuration now needs to be enabled explicitly. Calls to the JndiLookup will now return a constant string. Also, Log4j now limits the protocols by default to only java. The message lookups feature has been completely removed. Lookups in configuration still work.</p>
-<p>From version 2.16.0 (for Java 8), the message lookups feature has been completely removed. Lookups in configuration still work. Furthermore, Log4j now disables access to JNDI by default. Users are advised not to enable JNDI in Log4j 2.16.0. If the JMS Appender is required, use Log4j 2.12.2.</p></section><section>
-<h4><a name="Reference"></a>Reference</h4>
-<p>Please refer to the <a href="security.html#CVE-2021-44228">Security page</a> for mitigation measures for older versions of Log4j.</p></section></section></section><section>
<h2><a name="Features"></a>Features</h2><section>
<h3><a name="API_Separation"></a>API Separation</h3>
<p>The API for Log4j is separate from the implementation making it clear for application developers which classes and methods they can use while ensuring forward compatibility. This allows the Log4j team to improve the implementation safely and in a compatible manner.</p>
diff --git a/log4j-2.17.0/security.html b/log4j-2.17.0/security.html
index 3de8d8b..6ea9fd0 100644
--- a/log4j-2.17.0/security.html
+++ b/log4j-2.17.0/security.html
@@ -138,288 +138,294 @@
</div>
</div>
</header>
- <main id="bodyColumn" class="span10" >
-<!-- vim: set syn=markdown : -->
-<!--
- Licensed to the Apache Software Foundation (ASF) under one or more
- contributor license agreements. See the NOTICE file distributed with
- this work for additional information regarding copyright ownership.
- The ASF licenses this file to You under the Apache License, Version 2.0
- (the "License"); you may not use this file except in compliance with
- the License. You may obtain a copy of the License at
- http://www.apache.org/licenses/LICENSE-2.0
+ <main id="bodyColumn" class="span10" >
+ <!-- vim: set syn=markdown : -->
+ <!--
+ Licensed to the Apache Software Foundation (ASF) under one or more
+ contributor license agreements. See the NOTICE file distributed with
+ this work for additional information regarding copyright ownership.
+ The ASF licenses this file to You under the Apache License, Version 2.0
+ (the "License"); you may not use this file except in compliance with
+ the License. You may obtain a copy of the License at
- Unless required by applicable law or agreed to in writing, software
- distributed under the License is distributed on an "AS IS" BASIS,
- WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- See the License for the specific language governing permissions and
- limitations under the License.
--->
-<h1>Apache Log4j Security Vulnerabilities</h1>
-<p>This page lists all the security vulnerabilities fixed in released versions of Apache Log4j 2. Each vulnerability is given a <a href="#Security_Impact_Levels">security impact rating</a> by the <a class="externalLink" href="mailto:private@logging.apache.org">Apache Logging security team</a>. please note that this rating may vary from platform to platform. We also list the versions of Apache Log4j the flaw is known to affect, and where a flaw has not been verified list the version with [...]
-<p>Note: Vulnerabilities that are not Log4j vulnerabilities but have either been incorrectly reported against Log4j or where Log4j provides a workaround are listed at the end of this page.</p>
-<p>Please note that Log4j 1.x has reached end of life and is no longer supported. Vulnerabilities reported after August 2015 against Log4j 1.x were not checked and will not be fixed. Users should upgrade to Log4j 2 to obtain security fixes.</p>
-<p>Please note that binary patches are never provided. If you need to apply a source code patch, use the building instructions for the Apache Log4j version that you are using. For Log4j 2 this is BUILDING.md. This file can be found in the root subdirectory of a source distributive.</p>
-<p>If you need help on building or configuring Log4j or other help on following the instructions to mitigate the known vulnerabilities listed here, please send your questions to the public Log4j Users mailing list</p>
-<p>If you have encountered an unlisted security vulnerability or other unexpected behaviour that has security impact, or if the descriptions here are incomplete, please report them privately to the <a class="externalLink" href="mailto:private@logging.apache.org">Log4j Security Team</a>. Thank you.</p>
-<p><a name="CVE-2021-45105"></a><a name="cve-2021-45046"></a></p><section>
-<h2><a name="Fixed_in_Log4j_2.17.0_.28Java_8.29"></a><a name="log4j-2.17.0"></a> Fixed in Log4j 2.17.0 (Java 8)</h2>
-<p><a class="externalLink" href="https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-45105">CVE-2021-45105</a>:<br />
-Apache Log4j2 does not always protect from infinite recursion in lookup evaluation</p>
-<table border="0" class="table table-striped">
-<thead>
+ http://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+ -->
+ <h1>Apache Log4j Security Vulnerabilities</h1>
+ <p>This page lists all the security vulnerabilities fixed in released versions of Apache Log4j 2. Each vulnerability is given a <a href="#Security_Impact_Levels">security impact rating</a> by the <a class="externalLink" href="mailto:private@logging.apache.org">Apache Logging security team</a>. please note that this rating may vary from platform to platform. We also list the versions of Apache Log4j the flaw is known to affect, and where a flaw has not been verified list the [...]
+ <p>Note: Vulnerabilities that are not Log4j vulnerabilities but have either been incorrectly reported against Log4j or where Log4j provides a workaround are listed at the end of this page.</p>
+ <p>Please note that Log4j 1.x has reached end of life and is no longer supported. Vulnerabilities reported after August 2015 against Log4j 1.x were not checked and will not be fixed. Users should upgrade to Log4j 2 to obtain security fixes.</p>
+ <p>Please note that binary patches are never provided. If you need to apply a source code patch, use the building instructions for the Apache Log4j version that you are using. For Log4j 2 this is BUILDING.md. This file can be found in the root subdirectory of a source distributive.</p>
+ <p>If you need help on building or configuring Log4j or other help on following the instructions to mitigate the known vulnerabilities listed here, please send your questions to the public Log4j Users mailing list</p>
+ <p>If you have encountered an unlisted security vulnerability or other unexpected behaviour that has security impact, or if the descriptions here are incomplete, please report them privately to the <a class="externalLink" href="mailto:private@logging.apache.org">Log4j Security Team</a>. Thank you.</p>
+ <p><a name="CVE-2021-45105"></a><a name="cve-2021-45046"></a></p><section>
+ <h2><a name="Fixed_in_Log4j_2.17.0_.28Java_8.29.2C_2.12.3_.28Java_7.29_and_2.3.1_.28Java_6.29"></a><a name="log4j-2.17.0"></a> Fixed in Log4j 2.17.0 (Java 8), 2.12.3 (Java 7) and 2.3.1 (Java 6)</h2>
+ <p><a class="externalLink" href="https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-45105">CVE-2021-45105</a>:<br />
+ Apache Log4j2 does not always protect from infinite recursion in lookup evaluation</p>
+ <table border="0" class="table table-striped">
+ <thead>
+
+ <tr class="a">
+ <th> <a class="externalLink" href="https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-45105">CVE-2021-45105</a> </th>
+ <th> Denial of Service </th></tr>
+ </thead><tbody>
+
+ <tr class="b">
+ <td> Severity </td>
+ <td> High </td></tr>
+ <tr class="a">
+ <td> Base CVSS Score </td>
+ <td> 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H) </td></tr>
+ <tr class="b">
+ <td> Versions Affected </td>
+ <td> All versions from 2.0-beta9 to 2.16.0, excluding 2.12.3 </td></tr>
+ </tbody>
+ </table><section>
+ <h3><a name="Description"></a>Description</h3>
+ <p>Apache Log4j2 versions 2.0-alpha1 through 2.16.0, excluding 2.12.3, did not protect from uncontrolled recursion from self-referential lookups. When the logging configuration uses a non-default Pattern Layout with a Context Lookup (for example, $${ctx:loginId}), attackers with control over Thread Context Map (MDC) input data can craft malicious input data that contains a recursive lookup, resulting in a StackOverflowError that will terminate the process. This is also know [...]
+ <h3><a name="Mitigation"></a>Mitigation</h3><section>
+ <h4><a name="Log4j_1.x_mitigation"></a>Log4j 1.x mitigation</h4>
+ <p>Log4j 1.x is not impacted by this vulnerability.</p></section><section>
+ <h4><a name="Log4j_2.x_mitigation"></a>Log4j 2.x mitigation</h4>
+ <p>Upgrade to Log4j 2.3.1 (for Java 6), 2.12.3 (for Java 7), or 2.17.0 (for Java 8 and later).</p>
+ <p>Alternatively, this infinite recursion issue can be mitigated in configuration:</p>
+ <ul>
-<tr class="a">
-<th> <a class="externalLink" href="https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-45105">CVE-2021-45105</a> </th>
-<th> Denial of Service </th></tr>
-</thead><tbody>
+ <li>In PatternLayout in the logging configuration, replace Context Lookups like ${ctx:loginId} or $${ctx:loginId} with Thread Context Map patterns (%X, %mdc, or %MDC).</li>
+ <li>Otherwise, in the configuration, remove references to Context Lookups like ${ctx:loginId} or $${ctx:loginId} where they originate from sources external to the application such as HTTP headers or user input.</li>
+ </ul>
+ <p>Note that only the log4j-core JAR file is impacted by this vulnerability. Applications using only the log4j-api JAR file without the log4j-core JAR file are not impacted by this vulnerability.</p>
+ <p>Also note that Apache Log4j is the only Logging Services subproject affected by this vulnerability. Other projects like Log4net and Log4cxx are not impacted by this.</p></section></section><section>
+ <h3><a name="Release_Details"></a>Release Details</h3>
+ <p>From version 2.17.0, (and 2.12.3 and 2.3.1 for Java 7 and Java 6), only lookup strings in configuration are expanded recursively; in any other usage, only the top-level lookup is resolved, and any nested lookups are not resolved.</p>
+ <p>The property to enable JNDI has been renamed from ‘log4j2.enableJndi’ to three separate properties: ‘log4j2.enableJndiLookup’, ‘log4j2.enableJndiJms’, and ‘log4j2.enableJndiContextSelector’.</p>
+ <p>JNDI functionality has been hardened in these versions: 2.3.1, 2.12.2, 2.12.3 or 2.17.0: from these versions onwards, support for the LDAP protocol has been removed and only the JAVA protocol is supported in JNDI connections.</p></section><section>
+ <h3><a name="Work_in_progress"></a>Work in progress</h3>
+ <p>The Log4j team will continue to actively update this page as more information becomes known.</p></section><section>
+ <h3><a name="Credit"></a>Credit</h3>
+ <p>Independently discovered by Hideki Okamoto of Akamai Technologies, Guy Lederfein of Trend Micro Research working with Trend Micro’s Zero Day Initiative, and another anonymous vulnerability researcher.</p></section><section>
+ <h3><a name="References"></a>References</h3>
+ <ul>
-<tr class="b">
-<td> Severity </td>
-<td> High </td></tr>
-<tr class="a">
-<td> Base CVSS Score </td>
-<td> 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H) </td></tr>
-<tr class="b">
-<td> Versions Affected </td>
-<td> All versions from 2.0-beta9 to 2.16.0 </td></tr>
-</tbody>
-</table><section>
-<h3><a name="Description"></a>Description</h3>
-<p>Apache Log4j2 versions 2.0-alpha1 through 2.16.0 did not protect from uncontrolled recursion from self-referential lookups. When the logging configuration uses a non-default Pattern Layout with a Context Lookup (for example, $${ctx:loginId}), attackers with control over Thread Context Map (MDC) input data can craft malicious input data that contains a recursive lookup, resulting in a StackOverflowError that will terminate the process. This is also known as a DOS (Denial of Service) at [...]
-<h3><a name="Mitigation"></a>Mitigation</h3><section>
-<h4><a name="Log4j_1.x_mitigation"></a>Log4j 1.x mitigation</h4>
-<p>Log4j 1.x is not impacted by this vulnerability.</p></section><section>
-<h4><a name="Log4j_2.x_mitigation"></a>Log4j 2.x mitigation</h4>
-<p>Implement one of the following mitigation techniques:</p>
-<ul>
+ <li><a class="externalLink" href="https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-45105">CVE-2021-45105</a></li>
+ <li><a class="externalLink" href="https://issues.apache.org/jira/browse/LOG4J2-3230">LOG4J2-3230</a></li>
+ </ul>
+ <p><a name="CVE-2021-45046"></a><a name="cve-2021-45046"></a></p></section></section><section>
+ <h2><a name="Fixed_in_Log4j_2.16.0_.28Java_8.29_and_Log4j_2.12.2_.28Java_7.29"></a><a name="log4j-2.16.0"></a> Fixed in Log4j 2.16.0 (Java 8) and Log4j 2.12.2 (Java 7)</h2>
+ <p><a class="externalLink" href="https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-45046">CVE-2021-45046</a>:<br />
+ Apache Log4j2 Thread Context Lookup Pattern vulnerable to remote code execution in certain non-default configurations</p>
+ <table border="0" class="table table-striped">
+ <thead>
-<li>Java 8 (or later) users should upgrade to release 2.17.0.</li>
-</ul>
-<p>Alternatively, this can be mitigated in configuration:</p>
-<ul>
+ <tr class="a">
+ <th> <a class="externalLink" href="https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-45046">CVE-2021-45046</a> </th>
+ <th> Remote Code Execution </th></tr>
+ </thead><tbody>
-<li>In PatternLayout in the logging configuration, replace Context Lookups like ${ctx:loginId} or $${ctx:loginId} with Thread Context Map patterns (%X, %mdc, or %MDC).</li>
-<li>Otherwise, in the configuration, remove references to Context Lookups like ${ctx:loginId} or $${ctx:loginId} where they originate from sources external to the application such as HTTP headers or user input.</li>
-</ul>
-<p>Note that only the log4j-core JAR file is impacted by this vulnerability. Applications using only the log4j-api JAR file without the log4j-core JAR file are not impacted by this vulnerability.</p>
-<p>Also note that Apache Log4j is the only Logging Services subproject affected by this vulnerability. Other projects like Log4net and Log4cxx are not impacted by this.</p></section></section><section>
-<h3><a name="Work_in_progress"></a>Work in progress</h3>
-<p>The Log4j team will continue to actively update this page as more information becomes known.</p></section><section>
-<h3><a name="Credit"></a>Credit</h3>
-<p>Independently discovered by Hideki Okamoto of Akamai Technologies, Guy Lederfein of Trend Micro Research working with Trend Micro’s Zero Day Initiative, and another anonymous vulnerability researcher.</p></section><section>
-<h3><a name="References"></a>References</h3>
-<ul>
+ <tr class="b">
+ <td> Severity </td>
+ <td> Critical </td></tr>
+ <tr class="a">
+ <td> Base CVSS Score </td>
+ <td> 9.0 (AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H) </td></tr>
+ <tr class="b">
+ <td> Versions Affected </td>
+ <td> All versions from 2.0-beta9 to 2.15.0, excluding 2.12.2 </td></tr>
+ </tbody>
+ </table><section>
+ <h3><a name="Description"></a>Description</h3>
+ <p>It was found that the fix to address <a class="externalLink" href="https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-44228">CVE-2021-44228</a> in Apache Log4j 2.15.0 was incomplete in certain non-default configurations. When the logging configuration uses a non-default Pattern Layout with a Context Lookup (for example, $${ctx:loginId}), attackers with control over Thread Context Map (MDC) input data can craft malicious input data using a JNDI Lookup pattern, result [...]
+ <h3><a name="Mitigation"></a>Mitigation</h3><section>
+ <h4><a name="Log4j_1.x_mitigation"></a>Log4j 1.x mitigation</h4>
+ <p>Log4j 1.x is not impacted by this vulnerability.</p></section><section>
+ <h4><a name="Log4j_2.x_mitigation"></a>Log4j 2.x mitigation</h4>
+ <p>Implement one of the following mitigation techniques:</p>
+ <ul>
-<li><a class="externalLink" href="https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-45105">CVE-2021-45105</a></li>
-<li><a class="externalLink" href="https://issues.apache.org/jira/browse/LOG4J2-3230">LOG4J2-3230</a></li>
-</ul>
-<p><a name="CVE-2021-45046"></a><a name="cve-2021-45046"></a></p></section></section><section>
-<h2><a name="Fixed_in_Log4j_2.12.2_.28Java_7.29_and_Log4j_2.16.0_.28Java_8.29"></a><a name="log4j-2.16.0"></a> Fixed in Log4j 2.12.2 (Java 7) and Log4j 2.16.0 (Java 8)</h2>
-<p><a class="externalLink" href="https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-45046">CVE-2021-45046</a>:<br />
-Apache Log4j2 Thread Context Lookup Pattern vulnerable to remote code execution in certain non-default configurations</p>
-<table border="0" class="table table-striped">
-<thead>
+ <li>Upgrade to Log4j 2.3.1 (for Java 6), 2.12.3 (for Java 7), or 2.17.0 (for Java 8 and later).</li>
+ <li>Otherwise, in any release other than 2.16.0, you may remove the JndiLookup class from the classpath: zip -q -d log4j-core-*.jar org/apache/logging/log4j/core/lookup/JndiLookup.class</li>
+ </ul>
+ <p>Users are advised not to enable JNDI in Log4j 2.16.0, since it still allows LDAP connections. If the JMS Appender is required, use one of these versions: 2.3.1, 2.12.2, 2.12.3 or 2.17.0: from these versions onwards, only the JAVA protocol is supported in JNDI connections.</p>
+ <p>Note that only the log4j-core JAR file is impacted by this vulnerability. Applications using only the log4j-api JAR file without the log4j-core JAR file are not impacted by this vulnerability.</p>
+ <p>Also note that Apache Log4j is the only Logging Services subproject affected by this vulnerability. Other projects like Log4net and Log4cxx are not impacted by this.</p></section></section><section>
+ <h3><a name="History"></a>History</h3>
+ <p><b>Severity is now Critical</b></p>
+ <p>The original severity of this CVE was rated as Moderate; since this CVE was published security experts found additional exploits against the Log4j 2.15.0 release, that could lead to information leaks, RCE (remote code execution) and LCE (local code execution) attacks.</p>
+ <p>Base CVSS Score changed from 3.7 (AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L) to 9.0 (AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H).</p>
+ <p>The title of this CVE was changed from mentioning Denial of Service attacks to mentioning Remote Code Execution attacks.</p>
+ <p>Only Pattern Layouts with a Context Lookup (for example, $${ctx:loginId}) are vulnerable to this. This page previously incorrectly mentioned that Thread Context Map pattern (%X, %mdc, or %MDC) in the layout would also allow this vulnerability.</p>
+ <p>While Log4j 2.15.0 makes a best-effort attempt to restrict JNDI LDAP lookups to localhost by default, there are ways to bypass this and users should not rely on this.</p>
+ <p><b>Older (discredited) mitigation measures</b></p>
+ <p>This page previously mentioned other mitigation measures, but we discovered that these measures only limit exposure while leaving some attack vectors open.</p>
+ <p>Other insufficient mitigation measures are: setting system property log4j2.formatMsgNoLookups or environment variable LOG4J_FORMAT_MSG_NO_LOOKUPS to true for releases >= 2.10, or modifying the logging configuration to disable message lookups with %m{nolookups}, %msg{nolookups} or %message{nolookups} for releases >= 2.7 and <= 2.14.1.</p>
+ <p>The reason these measures are insufficient is that, in addition to the Thread Context attack vector mentioned above, there are still code paths in Log4j where message lookups could occur: known examples are applications that use Logger.printf("%s", userInput), or applications that use a custom message factory, where the resulting messages do not implement StringBuilderFormattable. There may be other attack vectors.</p>
+ <p>The safest thing to do is to upgrade Log4j to a safe version, or remove the JndiLookup class from the log4j-core jar.</p></section><section>
+ <h3><a name="Release_Details"></a>Release Details</h3>
+ <p>From version 2.16.0 (for Java 8), the message lookups feature has been completely removed. Lookups in configuration still work. Furthermore, Log4j now disables access to JNDI by default. JNDI lookups in configuration now need to be enabled explicitly. Users are advised not to enable JNDI in Log4j 2.16.0, since it still allows LDAP connections. If the JMS Appender is required, use one of these versions: 2.3.1, 2.12.2, 2.12.3 or 2.17.0: from these versions onwards, only th [...]
+ <p>From version 2.12.2 (for Java 7) and 2.3.1 (for Java 6), the message lookups feature has been completely removed. Lookups in configuration still work. Furthermore, Log4j now disables access to JNDI by default. JNDI lookups in configuration now need to be enabled explicitly. When enabled, JNDI will only support the JAVA protocol, support for the LDAP protocol has been removed.</p>
+ <p>From version 2.17.0 (for Java 8), support for the LDAP protocol has been removed and only the JAVA protocol is supported in JNDI connections.</p>
+ <p>From version 2.17.0 (for Java 8), 2.12.3 (for Java 7) and 2.3.1 (for Java 6), the property to enable JNDI has been renamed from ‘log4j2.enableJndi’ to three separate properties: ‘log4j2.enableJndiLookup’, ‘log4j2.enableJndiJms’, and ‘log4j2.enableJndiContextSelector’.</p></section><section>
+ <h3><a name="Work_in_progress"></a>Work in progress</h3>
+ <p>The Log4j team will continue to actively update this page as more information becomes known.</p></section><section>
+ <h3><a name="Credit"></a>Credit</h3>
+ <p>This issue was discovered by Kai Mindermann of iC Consult and separately by 4ra1n.</p>
+ <p>Additional vulnerability details discovered independently by Ash Fox of Google, Alvaro Muñoz and Tony Torralba from GitHub, Anthony Weems of Praetorian, and RyotaK (@ryotkak).</p></section><section>
+ <h3><a name="References"></a>References</h3>
+ <ul>
-<tr class="a">
-<th> <a class="externalLink" href="https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-45046">CVE-2021-45046</a> </th>
-<th> Remote Code Execution </th></tr>
-</thead><tbody>
+ <li><a class="externalLink" href="https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-45046">CVE-2021-45046</a></li>
+ <li><a class="externalLink" href="https://issues.apache.org/jira/browse/LOG4J2-3221">LOG4J2-3221</a></li>
+ </ul>
+ <p><a name="CVE-2021-44228"></a><a name="cve-2021-44228"></a></p></section></section><section>
+ <h2><a name="Fixed_in_Log4j_2.15.0_.28Java_8.29"></a><a name="log4j-2.15.0"></a> Fixed in Log4j 2.15.0 (Java 8)</h2>
+ <p><a class="externalLink" href="https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-44228">CVE-2021-44228</a>: Apache Log4j2 JNDI features do not protect against attacker controlled LDAP and other JNDI related endpoints.</p>
+ <table border="0" class="table table-striped">
+ <thead>
-<tr class="b">
-<td> Severity </td>
-<td> Critical </td></tr>
-<tr class="a">
-<td> Base CVSS Score </td>
-<td> 9.0 (AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H) </td></tr>
-<tr class="b">
-<td> Versions Affected </td>
-<td> All versions from 2.0-beta9 to 2.15.0, excluding 2.12.2 </td></tr>
-</tbody>
-</table><section>
-<h3><a name="Description"></a>Description</h3>
-<p>It was found that the fix to address <a class="externalLink" href="https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-44228">CVE-2021-44228</a> in Apache Log4j 2.15.0 was incomplete in certain non-default configurations. When the logging configuration uses a non-default Pattern Layout with a Context Lookup (for example, $${ctx:loginId}), attackers with control over Thread Context Map (MDC) input data can craft malicious input data using a JNDI Lookup pattern, resulting in an info [...]
-<h3><a name="Mitigation"></a>Mitigation</h3><section>
-<h4><a name="Log4j_1.x_mitigation"></a>Log4j 1.x mitigation</h4>
-<p>Log4j 1.x is not impacted by this vulnerability.</p></section><section>
-<h4><a name="Log4j_2.x_mitigation"></a>Log4j 2.x mitigation</h4>
-<p>Implement one of the following mitigation techniques:</p>
-<ul>
+ <tr class="a">
+ <th><a class="externalLink" href="https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-44228">CVE-2021-44228</a> </th>
+ <th> Remote Code Execution </th></tr>
+ </thead><tbody>
-<li>Java 8 (or later) users should upgrade to release 2.16.0.</li>
-<li>Java 7 users should upgrade to release 2.12.2.</li>
-<li>Otherwise, in any release other than 2.16.0, you may remove the JndiLookup class from the classpath: zip -q -d log4j-core-*.jar org/apache/logging/log4j/core/lookup/JndiLookup.class</li>
-</ul>
-<p>Users are advised not to enable JNDI in Log4j 2.16.0. If the JMS Appender is required, use Log4j 2.12.2.</p>
-<p>Note that only the log4j-core JAR file is impacted by this vulnerability. Applications using only the log4j-api JAR file without the log4j-core JAR file are not impacted by this vulnerability.</p>
-<p>Also note that Apache Log4j is the only Logging Services subproject affected by this vulnerability. Other projects like Log4net and Log4cxx are not impacted by this.</p></section></section><section>
-<h3><a name="History"></a>History</h3>
-<p><b>Severity is now Critical</b></p>
-<p>The original severity of this CVE was rated as Moderate; since this CVE was published security experts found additional exploits against the Log4j 2.15.0 release, that could lead to information leaks, RCE (remote code execution) and LCE (local code execution) attacks.</p>
-<p>Base CVSS Score changed from 3.7 (AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L) to 9.0 (AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H).</p>
-<p>The title of this CVE was changed from mentioning Denial of Service attacks to mentioning Remote Code Execution attacks.</p>
-<p>Only Pattern Layouts with a Context Lookup (for example, $${ctx:loginId}) are vulnerable to this. This page previously incorrectly mentioned that Thread Context Map pattern (%X, %mdc, or %MDC) in the layout would also allow this vulnerability.</p>
-<p>While Log4j 2.15.0 makes a best-effort attempt to restrict JNDI LDAP lookups to localhost by default, there are ways to bypass this and users should not rely on this.</p>
-<p><b>Older (discredited) mitigation measures</b></p>
-<p>This page previously mentioned other mitigation measures, but we discovered that these measures only limit exposure while leaving some attack vectors open.</p>
-<p>Other insufficient mitigation measures are: setting system property log4j2.formatMsgNoLookups or environment variable LOG4J_FORMAT_MSG_NO_LOOKUPS to true for releases >= 2.10, or modifying the logging configuration to disable message lookups with %m{nolookups}, %msg{nolookups} or %message{nolookups} for releases >= 2.7 and <= 2.14.1.</p>
-<p>The reason these measures are insufficient is that, in addition to the Thread Context attack vector mentioned above, there are still code paths in Log4j where message lookups could occur: known examples are applications that use Logger.printf("%s", userInput), or applications that use a custom message factory, where the resulting messages do not implement StringBuilderFormattable. There may be other attack vectors.</p>
-<p>The safest thing to do is to upgrade Log4j to a safe version, or remove the JndiLookup class from the log4j-core jar.</p></section><section>
-<h3><a name="Release_Details"></a>Release Details</h3>
-<p>From version 2.16.0 (for Java 8), the message lookups feature has been completely removed. Lookups in configuration still work. Furthermore, Log4j now disables access to JNDI by default. JNDI lookups in configuration now need to be enabled explicitly. Users are advised not to enable JNDI in Log4j 2.16.0. If the JMS Appender is required, use Log4j 2.12.2.</p>
-<p>From version 2.12.2 (for Java 7), the message lookups feature has been completely removed. Lookups in configuration still work. Furthermore, Log4j now disables access to JNDI by default. JNDI lookups in configuration now need to be enabled explicitly. When enabled, JNDI will only support the java protocol.</p></section><section>
-<h3><a name="Work_in_progress"></a>Work in progress</h3>
-<p>The Log4j team will continue to actively update this page as more information becomes known.</p></section><section>
-<h3><a name="Credit"></a>Credit</h3>
-<p>This issue was discovered by Kai Mindermann of iC Consult and separately by 4ra1n.</p>
-<p>Additional vulnerability details discovered independently by Ash Fox of Google, Alvaro Muñoz and Tony Torralba from GitHub, Anthony Weems of Praetorian, and RyotaK (@ryotkak).</p></section><section>
-<h3><a name="References"></a>References</h3>
-<ul>
+ <tr class="b">
+ <td> Severity </td>
+ <td> Critical </td></tr>
+ <tr class="a">
+ <td> Base CVSS Score </td>
+ <td> 10.0 CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H </td></tr>
+ <tr class="b">
+ <td> Versions Affected </td>
+ <td> All versions from 2.0-beta9 to 2.14.1 </td></tr>
+ </tbody>
+ </table><section>
+ <h3><a name="Description"></a>Description</h3>
+ <p>In Apache Log4j2 versions up to and including 2.14.1 (excluding security releases 2.3.1, 2.12.2 and 2.12.3), the JNDI features used in configurations, log messages, and parameters do not protect against attacker-controlled LDAP and other JNDI related endpoints. An attacker who can control log messages or log message parameters can execute arbitrary code loaded from LDAP servers when message lookup substitution is enabled.</p></section><section>
+ <h3><a name="Mitigation"></a>Mitigation</h3><section>
+ <h4><a name="Log4j_1.x_mitigation"></a>Log4j 1.x mitigation</h4>
+ <p>Log4j 1.x does not have Lookups so the risk is lower. Applications using Log4j 1.x are only vulnerable to this attack when they use JNDI in their configuration. A separate CVE (CVE-2021-4104) has been filed for this vulnerability. To mitigate: Audit your logging configuration to ensure it has no JMSAppender configured. Log4j 1.x configurations without JMSAppender are not impacted by this vulnerability.</p></section><section>
+ <h4><a name="Log4j_2.x_mitigation"></a>Log4j 2.x mitigation</h4>
+ <p>Implement one of the following mitigation techniques:</p>
+ <ul>
-<li><a class="externalLink" href="https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-45046">CVE-2021-45046</a></li>
-<li><a class="externalLink" href="https://issues.apache.org/jira/browse/LOG4J2-3221">LOG4J2-3221</a></li>
-</ul>
-<p><a name="CVE-2021-44228"></a><a name="cve-2021-44228"></a></p></section></section><section>
-<h2><a name="Fixed_in_Log4j_2.15.0_.28Java_8.29"></a><a name="log4j-2.15.0"></a> Fixed in Log4j 2.15.0 (Java 8)</h2>
-<p><a class="externalLink" href="https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-44228">CVE-2021-44228</a>: Apache Log4j2 JNDI features do not protect against attacker controlled LDAP and other JNDI related endpoints.</p>
-<table border="0" class="table table-striped">
-<thead>
+ <li>Upgrade to Log4j 2.3.1 (for Java 6), 2.12.3 (for Java 7), or 2.17.0 (for Java 8 and later).</li>
+ <li>Otherwise, in any release other than 2.16.0, you may remove the JndiLookup class from the classpath: zip -q -d log4j-core-*.jar org/apache/logging/log4j/core/lookup/JndiLookup.class</li>
+ </ul>
+ <p>Note that only the log4j-core JAR file is impacted by this vulnerability. Applications using only the log4j-api JAR file without the log4j-core JAR file are not impacted by this vulnerability.</p>
+ <p>Also note that Apache Log4j is the only Logging Services subproject affected by this vulnerability. Other projects like Log4net and Log4cxx are not impacted by this.</p></section></section><section>
+ <h3><a name="History"></a>History</h3><section>
+ <h4><a name="Older_.28discredited.29_mitigation_measures"></a>Older (discredited) mitigation measures</h4>
+ <p>This page previously mentioned other mitigation measures, but we discovered that these measures only limit exposure while leaving some attack vectors open.</p>
+ <p>The 2.15.0 release was found to still be vulnerable when the configuration has a Pattern Layout containing a Context Lookup (for example, $${ctx:loginId}). When an attacker can control Thread Context values, they may inject a JNDI Lookup pattern, which will be evaluated and result in a JNDI connection. While Log4j 2.15.0 makes a best-effort attempt to restrict JNDI connections to localhost by default, there are ways to bypass this and users should not rely on this.</p>
+ <p>A new CVE (CVE-2021-45046, see above) was raised for this.</p>
+ <p>Other insufficient mitigation measures are: setting system property log4j2.formatMsgNoLookups or environment variable LOG4J_FORMAT_MSG_NO_LOOKUPS to true for releases >= 2.10, or modifying the logging configuration to disable message lookups with %m{nolookups}, %msg{nolookups} or %message{nolookups} for releases >= 2.7 and <= 2.14.1.</p>
+ <p>The reason these measures are insufficient is that, in addition to the Thread Context attack vector mentioned above, there are still code paths in Log4j where message lookups could occur: known examples are applications that use Logger.printf("%s", userInput), or applications that use a custom message factory, where the resulting messages do not implement StringBuilderFormattable. There may be other attack vectors.</p>
+ <p>The safest thing to do is to upgrade Log4j to a safe version, or remove the JndiLookup class from the log4j-core jar.</p></section><section>
+ <h4><a name="Release_Details"></a>Release Details</h4>
+ <p>As of Log4j 2.15.0 the message lookups feature was disabled by default. Lookups in configuration still work. While Log4j 2.15.0 has an option to enable Lookups in this fashion, users are strongly discouraged from enabling it. A whitelisting mechanism was introduced for JNDI connections, allowing only localhost by default. The 2.15.0 release was found to have additional vulnerabilities and is not recommended.</p>
+ <p>From version 2.16.0 (for Java 8), the message lookups feature has been completely removed. Lookups in configuration still work. Furthermore, Log4j now disables access to JNDI by default. JNDI lookups in configuration now need to be enabled explicitly. Users are advised not to enable JNDI in Log4j 2.16.0, since it still allows LDAP connections. If the JMS Appender is required, use one of these versions: 2.3.1, 2.12.2, 2.12.3 or 2.17.0: from these versions onwards, only th [...]
+ <p>From version 2.12.2 (for Java 7) and 2.3.1 (for Java 6), the message lookups feature has been completely removed. Lookups in configuration still work. Furthermore, Log4j now disables access to JNDI by default. JNDI lookups in configuration now need to be enabled explicitly. When enabled, JNDI will only support the JAVA protocol, support for the LDAP protocol has been removed.</p>
+ <p>From version 2.17.0 (for Java 8), support for the LDAP protocol has been removed and only the JAVA protocol is supported in JNDI connections.</p>
+ <p>From version 2.17.0 (for Java 8), 2.12.3 (for Java 7) and 2.3.1 (for Java 6), the property to enable JNDI has been renamed from ‘log4j2.enableJndi’ to three separate properties: ‘log4j2.enableJndiLookup’, ‘log4j2.enableJndiJms’, and ‘log4j2.enableJndiContextSelector’.</p></section></section><section>
+ <h3><a name="Work_in_progress"></a>Work in progress</h3>
+ <p>The Log4j team will continue to actively update this page as more information becomes known.</p></section><section>
+ <h3><a name="Credit"></a>Credit</h3>
+ <p>This issue was discovered by Chen Zhaojun of Alibaba Cloud Security Team.</p></section><section>
+ <h3><a name="References"></a>References</h3>
+ <ul>
-<tr class="a">
-<th><a class="externalLink" href="https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-44228">CVE-2021-44228</a> </th>
-<th> Remote Code Execution </th></tr>
-</thead><tbody>
+ <li><a class="externalLink" href="https://issues.apache.org/jira/browse/LOG4J2-3201">https://issues.apache.org/jira/browse/LOG4J2-3201</a></li>
+ <li><a class="externalLink" href="https://issues.apache.org/jira/browse/LOG4J2-3198">https://issues.apache.org/jira/browse/LOG4J2-3198</a>.</li>
+ </ul></section></section><section>
+ <h2><a name="Fixed_in_Log4j_2.13.2_.28Java_8.29"></a><a name="log4j-2.13.2"></a> Fixed in Log4j 2.13.2 (Java 8)</h2>
+ <p><a name="CVE-2020-9488"></a><a name="cve-2020-9488"></a> <a class="externalLink" href="https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-9488">CVE-2020-9488</a>: Improper validation of certificate with host mismatch in Apache Log4j SMTP appender.</p>
+ <table border="0" class="table table-striped">
+ <thead>
-<tr class="b">
-<td> Severity </td>
-<td> Critical </td></tr>
-<tr class="a">
-<td> Base CVSS Score </td>
-<td> 10.0 CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H </td></tr>
-<tr class="b">
-<td> Versions Affected </td>
-<td> All versions from 2.0-beta9 to 2.14.1 </td></tr>
-</tbody>
-</table><section>
-<h3><a name="Description"></a>Description</h3>
-<p>In Apache Log4j2 versions up to and including 2.14.1 (excluding security release 2.12.2), the JNDI features used in configurations, log messages, and parameters do not protect against attacker-controlled LDAP and other JNDI related endpoints. An attacker who can control log messages or log message parameters can execute arbitrary code loaded from LDAP servers when message lookup substitution is enabled.</p></section><section>
-<h3><a name="Mitigation"></a>Mitigation</h3><section>
-<h4><a name="Log4j_1.x_mitigation"></a>Log4j 1.x mitigation</h4>
-<p>Log4j 1.x does not have Lookups so the risk is lower. Applications using Log4j 1.x are only vulnerable to this attack when they use JNDI in their configuration. A separate CVE (CVE-2021-4104) has been filed for this vulnerability. To mitigate: Audit your logging configuration to ensure it has no JMSAppender configured. Log4j 1.x configurations without JMSAppender are not impacted by this vulnerability.</p></section><section>
-<h4><a name="Log4j_2.x_mitigation"></a>Log4j 2.x mitigation</h4>
-<p>Implement one of the following mitigation techniques:</p>
-<ul>
+ <tr class="a">
+ <th> <a class="externalLink" href="https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-9488">CVE-2020-9488</a> </th>
+ <th> </th></tr>
+ </thead><tbody>
-<li>Java 8 (or later) users should upgrade to release 2.16.0.</li>
-<li>Java 7 users should upgrade to release 2.12.2.</li>
-<li>Otherwise, in any release other than 2.16.0, you may remove the JndiLookup class from the classpath: zip -q -d log4j-core-*.jar org/apache/logging/log4j/core/lookup/JndiLookup.class</li>
-</ul>
-<p>Note that only the log4j-core JAR file is impacted by this vulnerability. Applications using only the log4j-api JAR file without the log4j-core JAR file are not impacted by this vulnerability.</p>
-<p>Also note that Apache Log4j is the only Logging Services subproject affected by this vulnerability. Other projects like Log4net and Log4cxx are not impacted by this.</p></section></section><section>
-<h3><a name="History"></a>History</h3><section>
-<h4><a name="Older_.28discredited.29_mitigation_measures"></a>Older (discredited) mitigation measures</h4>
-<p>This page previously mentioned other mitigation measures, but we discovered that these measures only limit exposure while leaving some attack vectors open.</p>
-<p>The 2.15.0 release was found to still be vulnerable when the configuration has a Pattern Layout containing a Context Lookup (for example, $${ctx:loginId}). When an attacker can control Thread Context values, they may inject a JNDI Lookup pattern, which will be evaluated and result in a JNDI connection. While Log4j 2.15.0 makes a best-effort attempt to restrict JNDI connections to localhost by default, there are ways to bypass this and users should not rely on this.</p>
-<p>A new CVE (CVE-2021-45046, see above) was raised for this.</p>
-<p>Other insufficient mitigation measures are: setting system property log4j2.formatMsgNoLookups or environment variable LOG4J_FORMAT_MSG_NO_LOOKUPS to true for releases >= 2.10, or modifying the logging configuration to disable message lookups with %m{nolookups}, %msg{nolookups} or %message{nolookups} for releases >= 2.7 and <= 2.14.1.</p>
-<p>The reason these measures are insufficient is that, in addition to the Thread Context attack vector mentioned above, there are still code paths in Log4j where message lookups could occur: known examples are applications that use Logger.printf("%s", userInput), or applications that use a custom message factory, where the resulting messages do not implement StringBuilderFormattable. There may be other attack vectors.</p>
-<p>The safest thing to do is to upgrade Log4j to a safe version, or remove the JndiLookup class from the log4j-core jar.</p></section><section>
-<h4><a name="Release_Details"></a>Release Details</h4>
-<p>As of Log4j 2.15.0 the message lookups feature was disabled by default. Lookups in configuration still work. While Log4j 2.15.0 has an option to enable Lookups in this fashion, users are strongly discouraged from enabling it. A whitelisting mechanism was introduced for JNDI connections, allowing only localhost by default. The 2.15.0 release was found to have additional vulnerabilities and is not recommended.</p>
-<p>From version 2.16.0 (for Java 8), the message lookups feature has been completely removed. Lookups in configuration still work. Furthermore, Log4j now disables access to JNDI by default. JNDI lookups in configuration now need to be enabled explicitly. Users are advised not to enable JNDI in Log4j 2.16.0. If the JMS Appender is required, use Log4j 2.12.2.</p>
-<p>From version 2.12.2 (for Java 7), the message lookups feature has been completely removed. Lookups in configuration still work. Furthermore, Log4j now disables access to JNDI by default. JNDI lookups in configuration now need to be enabled explicitly. When enabled, JNDI will only support the java protocol.</p></section></section><section>
-<h3><a name="Work_in_progress"></a>Work in progress</h3>
-<p>The Log4j team will continue to actively update this page as more information becomes known.</p></section><section>
-<h3><a name="Credit"></a>Credit</h3>
-<p>This issue was discovered by Chen Zhaojun of Alibaba Cloud Security Team.</p></section><section>
-<h3><a name="References"></a>References</h3>
-<ul>
+ <tr class="b">
+ <td> Severity </td>
+ <td> Low </td></tr>
+ <tr class="a">
+ <td> CVSS Base Score </td>
+ <td> 3.7 (Low) CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N </td></tr>
+ <tr class="b">
+ <td> Versions Affected </td>
+ <td> All versions from 2.0-alpha1 to 2.13.1 </td></tr>
+ </tbody>
+ </table><section>
+ <h3><a name="Description"></a>Description</h3>
+ <p>Improper validation of certificate with host mismatch in Log4j2 SMTP appender. This could allow an SMTPS connection to be intercepted by a man-in-the-middle attack which could leak any log messages sent through that appender.</p>
+ <p>The reported issue was caused by an error in SslConfiguration. Any element using SslConfiguration in the Log4j Configuration is also affected by this issue. This includes HttpAppender, SocketAppender, and SyslogAppender. Usages of SslConfiguration that are configured via system properties are not affected.</p></section><section>
+ <h3><a name="Mitigation"></a>Mitigation</h3>
+ <p>Users should upgrade to Apache Log4j 2.13.2 which fixed this issue in <a class="externalLink" href="https://issues.apache.org/jira/browse/LOG4J2-2819">https://issues.apache.org/jira/browse/LOG4J2-2819</a> by making SSL settings configurable for SMTPS mail sessions. As a workaround for previous releases, users can set the mail.smtp.ssl.checkserveridentity system property to true to enable SMTPS hostname verification for all SMTPS mail sessions.</p></section><section>
+ <h3><a name="Credit"></a>Credit</h3>
+ <p>This issues was discovered by Peter Stöckli.</p></section><section>
+ <h3><a name="References"></a>References</h3>
+ <ul>
-<li><a class="externalLink" href="https://issues.apache.org/jira/browse/LOG4J2-3201">https://issues.apache.org/jira/browse/LOG4J2-3201</a></li>
-<li><a class="externalLink" href="https://issues.apache.org/jira/browse/LOG4J2-3198">https://issues.apache.org/jira/browse/LOG4J2-3198</a>.</li>
-</ul></section></section><section>
-<h2><a name="Fixed_in_Log4j_2.13.2_.28Java_8.29"></a><a name="log4j-2.13.2"></a> Fixed in Log4j 2.13.2 (Java 8)</h2>
-<p><a name="CVE-2020-9488"></a><a name="cve-2020-9488"></a> <a class="externalLink" href="https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-9488">CVE-2020-9488</a>: Improper validation of certificate with host mismatch in Apache Log4j SMTP appender.</p>
-<table border="0" class="table table-striped">
-<thead>
+ <li><a class="externalLink" href="https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-9488">CVE-2020-9488</a></li>
+ <li><a class="externalLink" href="https://issues.apache.org/jira/browse/LOG4J2-2819">LOG4J2-2819</a></li>
+ </ul></section></section><section>
+ <h2><a name="Fixed_in_Log4j_2.8.2_.28Java_7.29"></a><a name="log4j-2.8.2"></a> Fixed in Log4j 2.8.2 (Java 7)</h2>
+ <p><a name="CVE-2017-5645"></a><a name="cve-2017-5645"></a> <a class="externalLink" href="https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-5645">CVE-2017-5645</a>: Apache Log4j socket receiver deserialization vulnerability.</p>
+ <table border="0" class="table table-striped">
+ <thead>
-<tr class="a">
-<th> <a class="externalLink" href="https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-9488">CVE-2020-9488</a> </th>
-<th> </th></tr>
-</thead><tbody>
+ <tr class="a">
+ <th> <a class="externalLink" href="https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-5645">CVE-2017-5645</a> </th>
+ <th> </th></tr>
+ </thead><tbody>
-<tr class="b">
-<td> Severity </td>
-<td> Low </td></tr>
-<tr class="a">
-<td> CVSS Base Score </td>
-<td> 3.7 (Low) CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N </td></tr>
-<tr class="b">
-<td> Versions Affected </td>
-<td> All versions from 2.0-alpha1 to 2.13.1 </td></tr>
-</tbody>
-</table><section>
-<h3><a name="Description"></a>Description</h3>
-<p>Improper validation of certificate with host mismatch in Log4j2 SMTP appender. This could allow an SMTPS connection to be intercepted by a man-in-the-middle attack which could leak any log messages sent through that appender.</p>
-<p>The reported issue was caused by an error in SslConfiguration. Any element using SslConfiguration in the Log4j Configuration is also affected by this issue. This includes HttpAppender, SocketAppender, and SyslogAppender. Usages of SslConfiguration that are configured via system properties are not affected.</p></section><section>
-<h3><a name="Mitigation"></a>Mitigation</h3>
-<p>Users should upgrade to Apache Log4j 2.13.2 which fixed this issue in <a class="externalLink" href="https://issues.apache.org/jira/browse/LOG4J2-2819">https://issues.apache.org/jira/browse/LOG4J2-2819</a> by making SSL settings configurable for SMTPS mail sessions. As a workaround for previous releases, users can set the mail.smtp.ssl.checkserveridentity system property to true to enable SMTPS hostname verification for all SMTPS mail sessions.</p></section><section>
-<h3><a name="Credit"></a>Credit</h3>
-<p>This issues was discovered by Peter Stöckli.</p></section><section>
-<h3><a name="References"></a>References</h3>
-<ul>
+ <tr class="b">
+ <td> Severity </td>
+ <td> Moderate </td></tr>
+ <tr class="a">
+ <td> CVSS Base Score </td>
+ <td> 7.5 (AV:N/AC:L/Au:N/C:P/I:P/A:P) </td></tr>
+ <tr class="b">
+ <td> Versions Affected </td>
+ <td> All versions from 2.0-alpha1 to 2.8.1 </td></tr>
+ </tbody>
+ </table><section>
+ <h3><a name="Description"></a>Description</h3>
+ <p>When using the TCP socket server or UDP socket server to receive serialized log events from another application, a specially crafted binary payload can be sent that, when deserialized, can execute arbitrary code.</p></section><section>
+ <h3><a name="Mitigation"></a>Mitigation</h3>
+ <p>Java 7 and above users should migrate to version 2.8.2 or avoid using the socket server classes. Java 6 users should avoid using the TCP or UDP socket server classes, or they can manually backport the <a class="externalLink" href="https://github.com/apache/logging-log4j2/commit/5dcc192">security fix commit</a> from 2.8.2.</p></section><section>
+ <h3><a name="Credit"></a>Credit</h3>
+ <p>This issue was discovered by Marcio Almeida de Macedo of Red Team at Telstra</p></section><section>
+ <h3><a name="References"></a>References</h3>
+ <ul>
-<li><a class="externalLink" href="https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-9488">CVE-2020-9488</a></li>
-<li><a class="externalLink" href="https://issues.apache.org/jira/browse/LOG4J2-2819">LOG4J2-2819</a></li>
-</ul></section></section><section>
-<h2><a name="Fixed_in_Log4j_2.8.2_.28Java_7.29"></a><a name="log4j-2.8.2"></a> Fixed in Log4j 2.8.2 (Java 7)</h2>
-<p><a name="CVE-2017-5645"></a><a name="cve-2017-5645"></a> <a class="externalLink" href="https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-5645">CVE-2017-5645</a>: Apache Log4j socket receiver deserialization vulnerability.</p>
-<table border="0" class="table table-striped">
-<thead>
+ <li><a class="externalLink" href="https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-5645">CVE-2017-5645</a></li>
+ <li><a class="externalLink" href="https://issues.apache.org/jira/browse/LOG4J2-1863">LOG4J2-1863</a></li>
+ <li><a class="externalLink" href="https://github.com/apache/logging-log4j2/commit/5dcc192">Security fix commit</a></li>
+ </ul></section></section><section>
+ <h2><a name="Summary_of_security_impact_levels_for_Apache_Log4j"></a><a name="Security_Impact_Levels"></a> Summary of security impact levels for Apache Log4j</h2>
+ <p>The Apache Log4j Security Team rates the impact of each security flaw that affects Log4j. We’ve chosen a rating scale quite similar to those used by other major vendors in order to be consistent. Basically the goal of the rating system is to answer the question “How worried should I be about this vulnerability?”.</p>
+ <p>Note that the rating chosen for each flaw is the worst possible case across all architectures. To determine the exact impact of a particular vulnerability on your own systems you will still need to read the security advisories to find out more about the flaw.</p>
+ <p>We use the following descriptions to decide on the impact rating to give each vulnerability:</p><section>
+ <h3><a name="Critical"></a>Critical</h3>
+ <p>A vulnerability rated with a Critical impact is one which could potentially be exploited by a remote attacker to get Log4j to execute arbitrary code (either as the user the server is running as, or root). These are the sorts of vulnerabilities that could be exploited automatically by worms.</p></section><section>
+ <h3><a name="Important"></a>Important</h3>
+ <p>A vulnerability rated as Important impact is one which could result in the compromise of data or availability of the server. For Log4j this includes issues that allow an easy remote denial of service (something that is out of proportion to the attack or with a lasting consequence), access to arbitrary files outside of the context root, or access to files that should be otherwise prevented by limits or authentication.</p></section><section>
+ <h3><a name="Moderate"></a>Moderate</h3>
+ <p>A vulnerability is likely to be rated as Moderate if there is significant mitigation to make the issue less of an impact. This might be because the flaw does not affect likely configurations, or it is a configuration that isn’t widely used.</p></section><section>
+ <h3><a name="Low"></a>Low</h3>
+ <p>All other security flaws are classed as a Low impact. This rating is used for issues that are believed to be extremely hard to exploit, or where an exploit gives minimal consequences.</p></section></section>
+ </main>
-<tr class="a">
-<th> <a class="externalLink" href="https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-5645">CVE-2017-5645</a> </th>
-<th> </th></tr>
-</thead><tbody>
-<tr class="b">
-<td> Severity </td>
-<td> Moderate </td></tr>
-<tr class="a">
-<td> CVSS Base Score </td>
-<td> 7.5 (AV:N/AC:L/Au:N/C:P/I:P/A:P) </td></tr>
-<tr class="b">
-<td> Versions Affected </td>
-<td> All versions from 2.0-alpha1 to 2.8.1 </td></tr>
-</tbody>
-</table><section>
-<h3><a name="Description"></a>Description</h3>
-<p>When using the TCP socket server or UDP socket server to receive serialized log events from another application, a specially crafted binary payload can be sent that, when deserialized, can execute arbitrary code.</p></section><section>
-<h3><a name="Mitigation"></a>Mitigation</h3>
-<p>Java 7 and above users should migrate to version 2.8.2 or avoid using the socket server classes. Java 6 users should avoid using the TCP or UDP socket server classes, or they can manually backport the <a class="externalLink" href="https://github.com/apache/logging-log4j2/commit/5dcc192">security fix commit</a> from 2.8.2.</p></section><section>
-<h3><a name="Credit"></a>Credit</h3>
-<p>This issue was discovered by Marcio Almeida de Macedo of Red Team at Telstra</p></section><section>
-<h3><a name="References"></a>References</h3>
-<ul>
-<li><a class="externalLink" href="https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-5645">CVE-2017-5645</a></li>
-<li><a class="externalLink" href="https://issues.apache.org/jira/browse/LOG4J2-1863">LOG4J2-1863</a></li>
-<li><a class="externalLink" href="https://github.com/apache/logging-log4j2/commit/5dcc192">Security fix commit</a></li>
-</ul></section></section><section>
-<h2><a name="Summary_of_security_impact_levels_for_Apache_Log4j"></a><a name="Security_Impact_Levels"></a> Summary of security impact levels for Apache Log4j</h2>
-<p>The Apache Log4j Security Team rates the impact of each security flaw that affects Log4j. We’ve chosen a rating scale quite similar to those used by other major vendors in order to be consistent. Basically the goal of the rating system is to answer the question “How worried should I be about this vulnerability?”.</p>
-<p>Note that the rating chosen for each flaw is the worst possible case across all architectures. To determine the exact impact of a particular vulnerability on your own systems you will still need to read the security advisories to find out more about the flaw.</p>
-<p>We use the following descriptions to decide on the impact rating to give each vulnerability:</p><section>
-<h3><a name="Critical"></a>Critical</h3>
-<p>A vulnerability rated with a Critical impact is one which could potentially be exploited by a remote attacker to get Log4j to execute arbitrary code (either as the user the server is running as, or root). These are the sorts of vulnerabilities that could be exploited automatically by worms.</p></section><section>
-<h3><a name="Important"></a>Important</h3>
-<p>A vulnerability rated as Important impact is one which could result in the compromise of data or availability of the server. For Log4j this includes issues that allow an easy remote denial of service (something that is out of proportion to the attack or with a lasting consequence), access to arbitrary files outside of the context root, or access to files that should be otherwise prevented by limits or authentication.</p></section><section>
-<h3><a name="Moderate"></a>Moderate</h3>
-<p>A vulnerability is likely to be rated as Moderate if there is significant mitigation to make the issue less of an impact. This might be because the flaw does not affect likely configurations, or it is a configuration that isn’t widely used.</p></section><section>
-<h3><a name="Low"></a>Low</h3>
-<p>All other security flaws are classed as a Low impact. This rating is used for issues that are believed to be extremely hard to exploit, or where an exploit gives minimal consequences.</p></section></section>
- </main>
</div>
</div>
<hr/>