In Apache httpd 2.0.23 to 2.0.65, 2.2.0 to 2.2.34, and 2.4.0 to 2.4.29,
mod_authnz_ldap, if configured with AuthLDAPCharsetConfig, uses the
Accept-Language header value to lookup the right charset encoding when
verifying the user's credentials. If the header value is not present in the
charset conversion table, a fallback mechanism is used to truncate it to a
two characters value to allow a quick retry (for example, 'en-US' is
truncated to 'en'). A header value of less than two characters forces an
out of bound write of one NUL byte to a memory location that is not part of
the string. In the worst case, quite unlikely, the process would crash
which could be used as a Denial of Service attack. In the more likely case,
this memory is already reserved for future use and the issue has no effect
at all.
Upstream:released (2.4.30)
Ubuntu 12.04 ESM (Precise Pangolin):needs-triage
Ubuntu 14.04 LTS (Trusty Tahr):released (2.4.7-1ubuntu4.20)
Ubuntu 16.04 LTS (Xenial Xerus):released (2.4.18-2ubuntu3.8)
Ubuntu 18.04 LTS (Bionic Beaver):released (2.4.29-1ubuntu4.1)
Ubuntu 18.10 (Cosmic Cuttlefish):released (2.4.29-1ubuntu4.1)
Ubuntu 19.04 (Disco Dingo):released (2.4.29-1ubuntu4.1)
Upstream: (2.4)
More Information

Updated: 2019-01-14 21:24:34 UTC (commit 51f9b73af244ba86b9321e46e526586c25a8e060)