[CVE-2018-1285] XXE vulnerability in Apache log4net

[Matt Sicker <ma...@apache.org>]

Summary: Apache log4net does not disable XML external entities when
parsing log4net configuration files. This could allow for XXE-based
attacks in applications that accept arbitrary configuration files from
users. [1]

Affected: log4net up to 2.0.8

Mitigation: as there are no further releases of log4net beyond 2.0.8,
and the Logging Services PMC has voted [2] to mark the project
dormant, users should not allow arbitrary configuration files to be
specified from untrusted sources. While this is arguably a
vulnerability, misuse of any framework allowing untrusted input to
configure things is always a bad idea.

[1]: https://issues.apache.org/jira/browse/LOG4NET-575
[2]: https://lists.apache.org/thread.html/r6691036b0f85419e8bc97f6f522b8c353dd250b0a329164167b021a6%40%3Cdev.logging.apache.org%3E

-- 
Matt Sicker
Secretary, Apache Software Foundation
VP Logging Services, ASF