GraphicsMagick encounter a read beyond an allocated heap buffer when reading CMYKA TIFF files which claim to offer fewer samples per pixel than required. A maliciously crafted file could cause the application to crash. Please see bug 611356 for details.
Probably only affected when "tiff" USE flag is set which isn't the default.
Upstream patch: https://sourceforge.net/p/graphicsmagick/code/ci/6156b4c2992d855ece6079653b3b93c3229fc4b8/
GLSA Vote: No
Cleanup tracked in bug #631562