The exif_convert_utf16_to_utf8 function in exif-entry.c in the EXIF Tag Parsing Library (aka libexif) before 0.6.21 allows remote attackers to cause a denial of service (out-of-bounds read) or possibly obtain sensitive information from process memory via crafted EXIF tags in an image.
http://www.ubuntu.com/usn/USN-1513-1
http://www.securityfocus.com/bid/54437
http://www.debian.org/security/2012/dsa-2559
http://sourceforge.net/mailarchive/message.php?msg_id=29534027
http://secunia.com/advisories/49988
http://rhn.redhat.com/errata/RHSA-2012-1255.html
http://lists.opensuse.org/opensuse-security-announce/2012-07/msg00015.html