gd_interpolation.c in the GD Graphics Library (aka libgd) before 2.1.1, as used in PHP before 5.5.36, 5.6.x before 5.6.22, and 7.x before 7.0.7, allows remote attackers to cause a denial of service (out-of-bounds read) or possibly have unspecified other impact via a crafted image that is mishandled by the imagescale function.
https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05240731
https://github.com/php/php-src/commit/7a1aac3343af85b4af4df5f8844946eaa27394ab?w=1
https://github.com/libgd/libgd/commit/4f65a3e4eedaffa1efcf9ee1eb08f0b504fbc31a
http://www.ubuntu.com/usn/USN-3030-1
http://www.securityfocus.com/bid/90859
http://www.openwall.com/lists/oss-security/2016/05/26/3
http://www.debian.org/security/2016/dsa-3602
http://www.debian.org/security/2016/dsa-3587
http://rhn.redhat.com/errata/RHSA-2016-2750.html