ImageMagick is free and open-source software used for editing and manipulating digital images. In versions prior to 7.1.2-0 and 6.9.13-26, in ImageMagick's "magick mogrify" command, specifying multiple consecutive "%d" format specifiers in a filename template causes internal pointer arithmetic to generate an address below the beginning of the stack buffer, resulting in a stack overflow through "vsnprintf()". Versions 7.1.2-0 and 6.9.13-26 fix the issue.