ImageMagick is a collection of tools and libraries for many image formats.
If you process an image with ImageMagick and don’t validate the file before (e.g. check magic byte), ImageMagick will call any coders found in the given file. So if ImageMagick will find Ghostscript for example, it will call Ghostscript.
Due to multiple -dSAFER sandbox bypass vulnerabilities in Ghostscript, this can lead to arbitrary code execution.
To mitigate this problem we install a policy.xml file by default which will disable PS, EPS, PDF, and XPS coders.
A remote attacker, by enticing a user to process a specially crafted image file, could execute arbitrary code with the privileges of the process or cause a Denial of Service condition.
There is no known workaround at this time.
All ImageMagick 6 users should upgrade to the latest version:
# emerge --sync
# emerge --ask --oneshot --verbose
">=media-gfx/imagemagick-6.9.10.10-r1"
All ImageMagick 7 users should upgrade to the latest version:
# emerge --sync
# emerge --ask --oneshot --verbose
">=media-gfx/imagemagick-7.0.8.10-r1"