USN-4316-1 fixed a vulnerability in GD Graphics Library. This update provides the corresponding update for Ubuntu 14.04 ESM.
Original advisory details:
It was discovered that GD Graphics Library incorrectly handled cloning an image. An attacker could possibly use this issue to cause GD Graphics Library to crash, resulting in a denial of service. (CVE-2018-14553)
It was discovered that GD Graphics Library incorrectly handled loading images from X bitmap format files. An attacker could possibly use this issue to cause GD Graphics Library to crash, resulting in a denial of service, or to disclose contents of the stack that has been left there by previous code. (CVE-2019-11038)