The exif_process_user_comment 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 (NULL pointer dereference and application crash) via a crafted JPEG image. http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2016-6292