The ReadMNGImage function in coders/png.c in GraphicsMagick 1.3.26 mishandles large MNG images, leading to an invalid memory read in the SetImageColorCallBack function in magick/image.c.

The ReadWMFImage function in coders/wmf.c in GraphicsMagick 1.3.26 has a use-after-free issue for data associated with exception reporting.

The ReadSUNImage function in coders/sun.c in GraphicsMagick 1.3.26 has a colormap heap-based buffer over-read.

The WriteOnePNGImage function in coders/png.c in GraphicsMagick 1.3.26 allows remote attackers to cause a denial of service (out-of-bounds read and application crash) via a crafted file, because the program's actual control flow was inconsistent with its indentation. This resulted in a logging statement executing outside of a loop, and consequently using an invalid array index corresponding to the loop's exit condition.

GraphicsMagick 1.3.26 has a heap overflow in the WriteRGBImage() function in coders/rgb.c when processing multiple frames that have non-identical widths.

GraphicsMagick 1.3.26 has a NULL pointer dereference in the WriteMAPImage() function in coders/map.c when processing a non-colormapped image, a different vulnerability than CVE-2017-11638.

GraphicsMagick 1.3.26 has a heap overflow in the WriteCMYKImage() function in coders/cmyk.c when processing multiple frames that have non-identical widths.

GraphicsMagick 1.3.26 has a Memory Leak in the PersistCache function in magick/pixel_cache.c during writing of Magick Persistent Cache (MPC) files.

GraphicsMagick 1.3.26 has a segmentation violation in the WriteMAPImage() function in coders/map.c when processing a non-colormapped image, a different vulnerability than CVE-2017-11642.

GraphicsMagick 1.3.26 has a NULL pointer dereference in the WritePCLImage() function in coders/pcl.c during writes of monochrome images.