Certain Red Hat Enterprise Linux (RHEL) 4 and 5 packages for OpenSSH, as signed in August 2008 using a legitimate Red Hat GPG key, contain an externally introduced modification (Trojan Horse) that allows the package authors to have an unknown impact. NOTE: since the malicious packages were not distributed from any official Red Hat sources, the scope of this issue is restricted to users who may have obtained these packages through unofficial distribution points. As of 20080827, no unofficial distributions of this software are known.

PHP before 5.3.4 accepts the \0 character in a pathname, which might allow context-dependent attackers to bypass intended access restrictions by placing a safe file extension after this character, as demonstrated by .php\0.jpg at the end of the argument to the file_exists function.

The parse_str function in (1) PHP, (2) Hardened-PHP, and (3) Suhosin, when called without a second parameter, might allow remote attackers to overwrite arbitrary variables by specifying variable names and values in the string to be parsed. NOTE: it is not clear whether this is a design limitation of the function or a bug in PHP, although it is likely to be regarded as a bug in Hardened-PHP and Suhosin.