CVE-2026-28688

A flaw was found in ImageMagick. Processing commands related to MSL writing, specifically cloning an image structure for output, can cause a heap use-after-free vulnerability and result in a denial of service.

To exploit this issue, an attacker needs to convince a user to process a specially crafted file that makes ImageMagick use the MSL encoder to write or output an image. The malicious file, usually an .msl script or an image designed to invoke MSL processing, will contain instructions to trigger the cloning process and the use-after-free issue, with no evidence it can cause arbitrary command execution. Due to these reasons, this flaw has been rated with a moderate severity.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

To mitigate this vulnerability, disable the vulnerable encoder by adding the following line to the ImageMagick policy.xml file, typically located in the directory /etc/ImageMagick-7/, /etc/ImageMagick-6/ or /etc/ImageMagick/:

<policy domain="coder" rights="none" pattern="MSL" />

To reduce the risk of exploitation, avoid processing untrusted MSL files with ImageMagick. If ImageMagick is deployed in a way that it processes files from untrusted sources automatically, consider running the application inside a container or a restricted sandbox environment to limit the potential security impact.