The mail function in PHP 4.x to 4.2.2 does not filter ASCII control characters from its arguments, which could allow remote attackers to modify mail message content, including mail headers, and possibly use PHP as a "spam proxy."

move_uploaded_file in PHP does not does not check for the base directory (open_basedir), which could allow remote attackers to upload files to unintended locations on the system.

PHP, when not configured with the "display_errors = Off" setting in php.ini, allows remote attackers to obtain the physical path for an include file via a trailing slash in a request to a directly accessible PHP program, which modifies the base path, causes the include directive to fail, and produces an error message that contains the path.

Safe Mode feature (safe_mode) in PHP 3.0 through 4.1.0 allows attackers with access to the MySQL database to bypass Safe Mode access restrictions and read arbitrary files using "LOAD DATA INFILE LOCAL" SQL statements.

PHP Apache module 4.0.4 and earlier allows remote attackers to bypass .htaccess access restrictions via a malformed HTTP request on an unrestricted page that causes PHP to use those access controls on the next page that is requested.

The Apache module for PHP 4.0.0 through PHP 4.0.4, when disabled with the 'engine = off' option for a virtual host, may disable PHP for other virtual hosts, which could cause Apache to serve the source code of PHP scripts.