CVE-2017-15710

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.