A flaw was found in gd as shipped with Fedora. Cloning a image with style "attached", triggers a NULL pointer dereference in 'gdImageClone' leading to denial of service.

Affected versions: gd-2.2.5 gd-2.2.4 gd-2.2.3 gd-2.2.2 gd-2.2.1 gd-2.2.0 gd-2.1.1 gd-2.1.0 gd-2.1.0-rc2

References:

https://bugzilla.redhat.com/showbug.cgi?id=1599032

gdinterpolation.c in the GD Graphics Library (aka libgd) before 2.1.1, as used in PHP before 5.5.36, 5.6.x before 5.6.22, and 7.x before 7.0.7, allows remote attackers to cause a denial of service (out-of-bounds read) or possibly have unspecified other impact via a crafted image that is mishandled by the imagescale function.