The IMAP functionality in PHP before 4.3.1 allows remote attackers to cause a denial of service via an e-mail message with a (1) To or (2) From header with an address that contains a large number of "\" (backslash) characters.

Buffer overflows in PHP before 4.3.3 have unknown impact and unknown attack vectors.

Integer overflows in (1) base64_encode and (2) the GD library for PHP before 4.3.3 have unknown impact and unknown attack vectors.

Cross-site scripting (XSS) vulnerability in the transparent SID support capability for PHP before 4.3.2 (session.use_trans_sid) allows remote attackers to insert arbitrary script via the PHPSESSID parameter.

The php_if_imap_mime_header_decode function in the IMAP functionality in PHP before 4.2.2 allows remote attackers to cause a denial of service (crash) via an e-mail header with a long "To" header.

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.

Argument injection vulnerability in the mail function for PHP 4.x to 4.2.2 may allow attackers to bypass safe mode restrictions and modify command line arguments to the MTA (e.g. sendmail) in the 5th argument to mail(), altering MTA behavior and possibly executing commands.