ImageMagick is "a suite of image manipulation tools (animate, composite, conjure, convert, display, identify, import, mogrify and montage) that are sometimes used by other applications for processing image files". Remote exploitation of multiple integer overflow vulnerabilities in ImageMagick, as included in various vendors' operating system distributions, allows attackers to crash applications using the ImageMagick library, and in some cases, execute arbitrary code.
Several integer overflow vulnerabilities have been identified in ImageMagick's handling of various file formats. By creating a specially crafted DCM, DIB, XBM, XCF, or XWD image file, an attacker can cause a heap buffer of insufficient size to be allocated. This results in a heap-based buffer overflow.
Analysis:
Exploitation of these vulnerabilities allows an attacker to crash the programs using ImageMagick library, or execute arbitrary code in the context of the user.
One way of exploiting these vulnerabilities is to persuade a targeted user to open a malicious image file with a program that utilizes the ImageMagick library.
As the tools that are part of ImageMagick are sometimes used as helper tools by other applications, this user may be the same as the web server user. This scenario is somewhat more severe than the previously described attack vector since the image processing can occur automatically.
Workaround:
Exposure to some of these vulnerabilities can be mitigated by moving or deleting the related module files. The file locations may vary between distributions. The globbing expressions listed below correspond to a Red Hat Linux system.