The htmlspecialchars function in PHP before 5.2.12 does not properly handle (1) overlong UTF-8 sequences, (2) invalid Shift_JIS sequences, and (3) invalid EUC-JP sequences, which allows remote attackers to conduct cross-site scripting (XSS) attacks by placing a crafted byte sequence before a special character.

PHP before 5.2.12 does not properly handle session data, which has unspecified impact and attack vectors related to (1) interrupt corruption of the SESSION superglobal array and (2) the session.save_path directive.

The zend_restore_ini_entry_cb function in zend_ini.c in PHP 5.3.0, 5.2.10, and earlier versions allows context-specific attackers to obtain sensitive information (memory contents) and cause a PHP crash by using the ini_set function to declare a variable, then using the ini_restore function to restore the variable.

The proc_open function in ext/standard/proc_open.c in PHP before 5.2.11 and 5.3.x before 5.3.1 does not enforce the (1) safe_mode_allowed_env_vars and (2) safe_mode_protected_env_vars directives, which allows context-dependent attackers to execute programs with an arbitrary environment via the env parameter, as demonstrated by a crafted value of the LD_LIBRARY_PATH environment variable.

The php_openssl_apply_verification_policy function in PHP before 5.2.11 does not properly perform certificate validation, which has unknown impact and attack vectors, probably related to an ability to spoof certificates.

Unspecified vulnerability in PHP before 5.2.11, and 5.3.x before 5.3.1, has unknown impact and attack vectors related to "missing sanity checks around exif processing."

Unspecified vulnerability in the imagecolortransparent function in PHP before 5.2.11 has unknown impact and attack vectors related to an incorrect "sanity check for the color index."

The JSON_parser function (ext/json/JSON_parser.c) in PHP 5.2.x before 5.2.9 allows remote attackers to cause a denial of service (segmentation fault) via a malformed string to the json_decode API function.

The php_zip_make_relative_path function in php_zip.c in PHP 5.2.x before 5.2.9 allows context-dependent attackers to cause a denial of service (crash) via a ZIP file that contains filenames with relative paths, which is not properly handled during extraction.

The resource system in PHP 5.0.0 through 5.2.1 allows context-dependent attackers to execute arbitrary code by interrupting the hash_update_file function via a userspace (1) error or (2) stream handler, which can then be used to destroy and modify internal resources. NOTE: it was later reported that PHP 5.2 through 5.2.13 and 5.3 through 5.3.2 are also affected.