The compress.bzip2:// URL wrapper provided by the bz2 extension in PHP before 4.4.7, and 5.x before 5.2.2, does not implement safemode or open_basedir checks, which allows remote attackers to read bzip2 archives located outside of the intended directories.
PHP 5.2.1 allows context-dependent attackers to read portions of heap memory by executing certain scripts with a serialized data input string beginning with S:, which does not properly track the number of input bytes being processed.
The cpdf_open function in the ClibPDF (cpdf) extension in PHP 4.4.6 allows context-dependent attackers to obtain sensitive information (script source code) via a long string in the second argument.