Integer overflow in the GetEXIFProperty function in magick/property.c in ImageMagick before 6.7.6-4 allows remote attackers to cause a denial of service (out-of-bounds read) via a large component count for certain EXIF tags in a JPEG image. NOTE: this vulnerability exists because of an incomplete fix for CVE-2012-0259.
The product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.