CVE-2007-1285 (The Zend Engine in PHP 4.x before 4.4.7, and 5.x before 5.2.2, allows remote attackers to cause a denial of service (stack exhaustion and PHP crash) via deeply nested arrays, which trigger deep recursion in the variable destruction routines.)
CVE-2007-0988 (The zend_hash_init function in PHP 5 before 5.2.1 and PHP 4 before 4.4.5, when running on a 64-bit platform, allows context-dependent attackers to cause a denial of service (infinite loop) by unserializing certain integer expressions, which only cause 32-bit arguments to be used after the check for a negative value, as demonstrated by an "a:2147483649:{" argument.)