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.

The shmop functions in PHP before 4.4.5, and before 5.2.1 in the 5.x series, do not verify that their arguments correspond to a shmop resource, which allows context-dependent attackers to read and write arbitrary memory locations via arguments associated with an inappropriate resource, as demonstrated by a GD Image resource.

The ovrimos_longreadlen function in the Ovrimos extension for PHP before 4.4.5 allows context-dependent attackers to write to arbitrary memory locations via the result_id and length arguments.

The ovrimos_close function in the Ovrimos extension for PHP before 4.4.5 can trigger efree of an arbitrary address, which might allow context-dependent attackers to execute arbitrary code.

The php_binary serialization handler in the session extension in PHP before 4.4.5, and 5.x before 5.2.1, allows context-dependent attackers to obtain sensitive information (memory contents) via a serialized variable entry with a large length value, which triggers a buffer over-read.

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.

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.

PHP before 4.4.3 and 5.x before 5.1.4 does not limit the character set of the session identifier (PHPSESSID) for third party session handlers, which might make it easier for remote attackers to exploit other vulnerabilities by inserting PHP code into the PHPSESSID, which is stored in the session file. NOTE: it could be argued that this not a vulnerability in PHP itself, rather a design limitation that enables certain attacks against session handlers that do not account for this limitation.

scanf.c in PHP 5.1.4 and earlier, and 4.4.3 and earlier, allows context-dependent attackers to execute arbitrary code via a sscanf PHP function call that performs argument swapping, which increments an index past the end of an array and triggers a buffer over-read.

The error_log function in basic_functions.c in PHP before 4.4.4 and 5.x before 5.1.5 allows local users to bypass safe mode and open_basedir restrictions via a "php://" or other scheme in the third argument, which disables safe mode.

zend_hash_del_key_or_index in zend_hash.c in PHP before 4.4.3 and 5.x before 5.1.3 can cause zend_hash_del to delete the wrong element, which prevents a variable from being unset even when the PHP unset function is called, which might cause the variable's value to be used in security-relevant operations.

Directory traversal vulnerability in file.c in PHP 4.4.2 and 5.1.2 allows local users to bypass open_basedir restrictions allows remote attackers to create files in arbitrary directories via the tempnam function.

The copy function in file.c in PHP 4.4.2 and 5.1.2 allows local users to bypass safe mode and read arbitrary files via a source argument containing a compress.zlib:// URI.

Multiple cross-site scripting (XSS) vulnerabilities in PHP 4.4.1 and 5.1.1, when display_errors and html_errors are on, allow remote attackers to inject arbitrary web script or HTML via inputs to PHP applications that are not filtered when they are included in the resulting error message.

The imap_header function in the IMAP functionality for PHP before 4.3.0 allows remote attackers to cause a denial of service via an e-mail message with a large number of "To" addresses, which triggers an error in the rfc822_write_address function.