http://nvd.nist.gov/nvd.cfm?cvename=CVE-2007-0770 "Buffer overflow in GraphicsMagick and ImageMagick allows user-assisted remote attackers to cause a denial of service and possibly execute arbitrary code via a PALM image that is not properly handled by the ReadPALMImage function in coders/palm.c. NOTE: this issue is due to an incomplete patch for CVE-2006-5456." CVE-2006-5456 says that it is an issue with < 1.1.7, but the discussion in bug 210921 refers to a post-1.1.7 GraphicsMagick, so whether this affects the FE GraphicsMagick package should be investigated.
I'm still not completely sure if this issue is actually exploitable in GraphicsMagick, as the handling is a tad different then with ImageMagick, but I adapted the ImageMagick Fix nevertheless.