PHPMailer 6.4.1 contains a possible remote code execution vulnerability through the $lang_path
parameter of the setLanguage()
method. If the $lang_path
parameter is passed unfiltered from user input, it can be set to a UNC path, and if an attacker is also able to create a remote mount on the server that the UNC path points to, a script file under their control may be executed.
Arbitrary code may be run by a remote attacker under the web server or PHP process running on Window hosts.
Mitigated in PHPMailer 6.5.0 by no longer treating translation files as PHP code, but by parsing their text content directly.
This approach avoids the possibility of executing unknown code while retaining backward compatibility. This isn’t ideal, so the current translation format is deprecated and will be replaced in the next major release.
Any of:
$lang_path
parameter of the setLanguage()
method.Reported by listensec.com via Tidelift.
If you have any questions or comments about this advisory:
github.com/FriendsOfPHP/security-advisories/blob/master/phpmailer/phpmailer/CVE-2021-34551.yaml
github.com/PHPMailer/PHPMailer/blob/master/SECURITY.md
github.com/PHPMailer/PHPMailer/commit/acd264bf17ff4ac5c915f0d4226dce8a9ea70bc3
github.com/PHPMailer/PHPMailer/releases/tag/v6.5.0
github.com/PHPMailer/PHPMailer/security/advisories/GHSA-7q44-r25x-wm4q
lists.fedoraproject.org/archives/list/[email protected]/message/3YRMWGA4VTMXFB22KICMB7YMFZNFV3EJ
lists.fedoraproject.org/archives/list/[email protected]/message/FJYSOFCUBS67J3TKR74SD3C454N7VTYM
nvd.nist.gov/vuln/detail/CVE-2021-34551