CVE-2019-12409: Apache Solr RCE vulnerability due to bad config default

[Jan Høydahl <ja...@cominvent.com>]

CVE-2019-12409: Apache Solr RCE vulnerability due to bad config default

Severity: High

Vendor:
The Apache Software Foundation

Versions Affected:
Solr 8.1.1 and 8.2.0 for Linux

Description:
The 8.1.1 and 8.2.0 releases of Apache Solr contain an insecure setting
for the ENABLE_REMOTE_JMX_OPTS configuration option in the default
solr.in.sh configuration file shipping with Solr.

Windows users are not affected.

If you use the default solr.in.sh file from the affected releases, then
JMX monitoring will be enabled and exposed on RMI_PORT (default=18983),
without any authentication. If this port is opened for inbound traffic
in your firewall, then anyone with network access to your Solr nodes
will be able to access JMX, which may in turn allow them to upload
malicious code for execution on the Solr server.

The vulnerability is already public [1] and mitigation steps were
announced on project mailing lists and news page [3] on August 14th,
without mentioning RCE at that time.

Mitigation:
Make sure your effective solr.in.sh file has ENABLE_REMOTE_JMX_OPTS set
to 'false' on every Solr node and then restart Solr. Note that the
effective solr.in.sh file may reside in /etc/defaults/ or another
location depending on the install. You can then validate that the
'com.sun.management.jmxremote*' family of properties are not listed in
the "Java Properties" section of the Solr Admin UI, or configured in a
secure way.

There is no need to upgrade or update any code.

Remember to follow the Solr Documentation's advice to never expose Solr
nodes directly in a hostile network environment.

Credit:
Matei "Mal" Badanoiu
Solr JIRA user 'jnyryan' (John)

References:
[1] https://issues.apache.org/jira/browse/SOLR-13647
[3] https://lucene.apache.org/solr/news.html

--
Jan Høydahl, Lucene PMC member