The exifprocessIFDinMAKERNOTE function in ext/exif/exif.c in PHP before 5.5.38, 5.6.x before 5.6.24, and 7.x before 7.0.9 allows remote attackers to cause a denial of service (out-of-bounds array access and memory corruption), obtain sensitive information from process memory, or possibly have unspecified other impact via a crafted JPEG image.