ImageMagick is free and open-source software used for editing and manipulating digital images. Prior to 7.1.2-18 and 6.9.13-43, due to an incorrect return value on certain platforms a pointer is incremented past the end of a buffer that is on the stack and that could result in an out of bounds write. Versions 7.1.2-18 and 6.9.13-43 patch the issue.