The session extension in PHP 4 before 4.4.5, and PHP 5 before 5.2.1, calculates the reference count for the session variables without considering the internal pointer from the session globals, which allows context-dependent attackers to execute arbitrary code via a crafted string in the session_register after unsetting HTTP_SESSION_VARS and _SESSION, which destroys the session data Hashtable.
PHP 4 before 4.4.5, and PHP 5 before 5.2.1, when register_globals is enabled, allows context-dependent attackers to execute arbitrary code via deserialization of session data, which overwrites arbitrary global variables, as demonstrated by calling session_decode on a string beginning with "_SESSION|s:39:".
The resource system in PHP 4.0.0 through 4.4.6 and 5.0.0 through 5.2.1 allows context-dependent attackers to execute arbitrary code by interrupting certain functions in the GD (ext/gd) extension and unspecified other extensions via a userspace error handler, which can be used to destroy and modify internal resources.
The mb_parse_str function in PHP 4.0.0 through 4.4.6 and 5.0.0 through 5.2.1 sets the internal register_globals flag and does not disable it in certain cases when a script terminates, which allows remote attackers to invoke available PHP scripts with register_globals functionality that is not detectable by these scripts, as demonstrated by forcing a memory_limit violation.
Double free vulnerability in PHP before 4.4.7, and 5.x before 5.2.2, allows context-dependent attackers to execute arbitrary code by interrupting the session_regenerate_id function, as demonstrated by calling a userspace error handler or triggering a memory limit violation.
Multiple buffer overflows in the (1) ibase_connect and (2) ibase_pconnect functions in the interbase extension in PHP 4.4.6 and earlier allow context-dependent attackers to execute arbitrary code via a long argument.
The array_user_key_compare function in PHP 4.4.6 and earlier, and 5.x up to 5.2.1, makes erroneous calls to zval_dtor, which triggers memory corruption and allows local users to bypass safe_mode and execute arbitrary code via a certain unset operation after array_user_key_compare has been called.
The zip:// URL wrapper provided by the PECL zip extension in PHP before 4.4.7, and 5.2.0 and 5.2.1, does not implement safemode or open_basedir checks, which allows remote attackers to read ZIP archives located outside of the intended directories.
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.
Buffer overflow in the snmpget function in the snmp extension in PHP 5.2.3 and earlier, including PHP 4.4.6 and probably other PHP 4 versions, allows context-dependent attackers to execute arbitrary code via a long value in the third argument (object id).