Common Vulnerabilities and Exposures assigned an identifier CVE-2007-3294 to the following vulnerability:
Multiple buffer overflows in libtidy, as used in the Tidy extension for PHP 5.2.3 and possibly other products, allow context-dependent attackers to execute arbitrary code via (1) a long second argument to the tidy_parse_string function or (2) an unspecified vector to the tidy_repair_string function. NOTE: this might only be an issue in environments where vsnprintf is implemented as a wrapper for vsprintf.
This issue does not affect php as shipped in Red Hat Enterprise Linux 2.1, 3, 4,
or 5, as those packages are not built with libtidy support.
php-tidy in Fedora does not demonstrate any problems with large arguments passed
to tidy functions.