This module exploits Remote Code Execution vulnerability (CVE-2023-41892) in Craft CMS which is a popular
content management system. Craft CMS versions between 4.0.0-RC1 - 4.4.14 are affected by this vulnerability
allowing attackers to execute arbitrary code remotely, potentially compromising the security and integrity
of the application.
The vulnerability occurs using a PHP object creation in the `\craft\controllers\ConditionsController` class
which allows to run arbitrary PHP code by escalating the object creation calling some methods available in
`\GuzzleHttp\Psr7\FnStream`. Using this vulnerability in combination with The Imagick Extension and MSL which
stands for Magick Scripting Language, a full RCE can be achieved. MSL is a built-in ImageMagick language that
facilitates the reading of images, performance of image processing tasks, and writing of results back
to the filesystem. This can be leveraged to create a dummy image containing malicious PHP code using the
Imagick constructor class delivering a webshell that can be accessed by the attacker, thereby executing the
malicious PHP code and gaining access to the system.
Because of this, any remote attacker, without authentication, can exploit this vulnerability to gain
access to the underlying operating system as the user that the web services are running as (typically www-data).
msf > use exploit/linux/http/craftcms_unauth_rce_cve_2023_41892
msf exploit(craftcms_unauth_rce_cve_2023_41892) > show targets
...targets...
msf exploit(craftcms_unauth_rce_cve_2023_41892) > set TARGET < target-id >
msf exploit(craftcms_unauth_rce_cve_2023_41892) > show options
...show and set options...
msf exploit(craftcms_unauth_rce_cve_2023_41892) > exploit
Vulmon