ImageMagick is free and open-source software used for editing and manipulating digital images. In versions prior to 7.1.2-27, a heap buffer over-write can occur in the fx operation by passing a crafted argument. This issue has been fixed in version 7.1.2-27.
https://github.com/ImageMagick/ImageMagick/security/advisories/GHSA-422r-8c97-xcg4