Apache HTTP Server Out-of-bounds Write Vulnerability - 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 user39s 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 39en-US39 is truncated to 39en39). 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.