The memory_limit functionality in PHP 4.x up to 4.3.7, and 5.x up to 5.0.0RC3, under certain conditions such as when register_globals is enabled, allows remote attackers to execute arbitrary code by triggering a memory_limit abort during execution of the zend_hash_init function and overwriting a HashTable destructor pointer before the initialization of key data structures is complete.
Exploitability
AV:NAC:HAu:NImpact
C:PI:PA:P5.1/AV:N/AC:H/Au:N/C:P/I:P/A:P