gdImageColorMatch in gd_color_match.c in the GD Graphics Library (aka LibGD) 2.2.5, as used in the imagecolormatch function in PHP before 5.6.40, 7.x before 7.1.26, 7.2.x before 7.2.14, and 7.3.x before 7.3.1, has a heap-based buffer overflow. This can be exploited by an attacker who is able to trigger imagecolormatch calls with crafted image data.

• https://nvd.nist.gov/vuln/detail/CVE-2019-6977
• https://bugs.php.net/bug.php?id=77270
• http://php.net/ChangeLog-7.php
• http://php.net/ChangeLog-5.php
• http://www.securityfocus.com/bid/106731
• https://lists.debian.org/debian-lts-announce/2019/01/msg00028.html
• https://www.debian.org/security/2019/dsa-4384
• https://usn.ubuntu.com/3900-1/
• https://security.netapp.com/advisory/ntap-20190315-0003/
• https://security.gentoo.org/glsa/201903-18
• http://lists.opensuse.org/opensuse-security-announce/2019-04/msg00025.html
• http://lists.opensuse.org/opensuse-security-announce/2019-04/msg00031.html
• http://packetstormsecurity.com/files/152459/PHP-7.2-imagecolormatch-Out-Of-Band-Heap-Write.html
• https://www.exploit-db.com/exploits/46677/
• https://access.redhat.com/errata/RHSA-2019:2519
• https://access.redhat.com/errata/RHSA-2019:3299
• https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/TEYUUOW75YD3DENIPYMO263E6NL2NFHI/
• https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/3WRUPZVT2MWFUEMVGTRAGDOBHLNMGK5R/
• https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/TTXSLRZI5BCQT3H5KALG3DHUWUMNPDX2/
• https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/3CZ2QADQTKRHTGB2AHD7J4QQNDLBEMM6/