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.
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.
PHP before 5.2.1 allows attackers to bypass safe_mode and open_basedir restrictions via unspecified vectors in the session extension. NOTE: it is possible that this issue is a duplicate of CVE-2006-6383.
Multiple buffer overflows in PHP before 5.2.1 allow attackers to cause a denial of service and possibly execute arbitrary code via unspecified vectors in the (1) session, (2) zip, (3) imap, and (4) sqlite extensions; (5) stream filters; and the (6) str_replace, (7) mail, (8) ibase_delete_user, (9) ibase_add_user, and (10) ibase_modify_user functions. NOTE: vector 6 might actually be an integer overflow (CVE-2007-1885). NOTE: as of 20070411, vector (3) might involve the imap_mail_compose function (CVE-2007-1825).
The WDDX deserializer in the wddx extension in PHP 5 before 5.2.1 and PHP 4 before 4.4.5 does not properly initialize the key_length variable for a numerical key, which allows context-dependent attackers to read stack memory via a wddxPacket element that contains a variable with a string name before a numerical variable.
Multiple format string vulnerabilities in PHP before 5.2.1 might allow attackers to execute arbitrary code via format string specifiers to (1) all of the *print functions on 64-bit systems, and (2) the odbc_result_all function.
PHP 5.2.0 and 4.4 allows local users to bypass safe_mode and open_basedir restrictions via a malicious path and a null byte before a ";" in a session_save_path argument, followed by an allowed path, which causes a parsing inconsistency in which PHP validates the allowed path but sets session.save_path to the malicious path.