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.

Affected: Ubuntu:14.04:LTS: libgd2, Ubuntu:16.04:LTS: libgd2

It was discovered that the GD library incorrectly handled memory when using gdImageScaleTwoPass(). A remote attacker could possibly use this issue to cause a denial of service. This issue only affected Ubuntu 14.04 LTS. (CVE-2013-7456)

It was discovered that the GD library incorrectly handled certain malformed XBM images. If a user or automated system were tricked into processing a specially crafted XBM image, an attacker could cause a denial of service. This issue only affected Ubuntu 14.04 LTS, Ubuntu 15.10 and Ubuntu 16.04 LTS. (CVE-2016-5116)

It was discovered that the GD library incorrectly handled memory when using _gd2GetHeader(). A remote attacker could possibly use this issue to cause a denial of service or possibly execute arbitrary code. (CVE-2016-5766)

It was discovered that the GD library incorrectly handled certain color indexes. A remote attacker could possibly use this issue to cause a denial of service. This issue only affected Ubuntu 14.04 LTS, Ubuntu 15.10 and Ubuntu 16.04 LTS. (CVE-2016-6128)

It was discovered that the GD library incorrectly handled memory when encoding a GIF image. A remote attacker could possibly use this issue to cause a denial of service. (CVE-2016-6161)