The remote Debian host is missing a security-related update.
Several issues have been discovered in ImageMagick, a popular set of programs and libraries for image manipulation. These issues include several problems in memory handling that can result in a denial of service attack or in execution of arbitrary code by an attacker with control on the image input.
Upgrade the imagemagick packages. For the stable distribution (jessie), these problems have been fixed in version 8:22.214.171.124-5+deb8u6.