Ubuntu security notices
USN-4966-2: libx11 vulnerability
USN-4966-2: libx11 vulnerability USN-4966-1 fixed a vulnerability in libx11. This update provides the corresponding update for Ubuntu 14.04 ESM and Ubuntu 16.04 ESM. Original advisory details: It was discovered that libx11 incorrectly validated certain parameter lengths. A remote attacker could possibly use this issue to trick libx11 into emitting extra X protocol requests. Source: USN-4966-2: libx11 vulnerability