Several security issues were fixed in the X.Org X server.
It was discovered that the X.Org X server incorrectly handled endianness conversion of certain X events. An attacker able to connect to an X server, either locally or remotely, could use this issue to crash the server, or possibly execute arbitrary code as an administrator. (CVE-2017-10971)
24 July 2017
A security issue affects these releases of Ubuntu and its derivatives:
Several security issues were fixed in the X.Org X server.
It was discovered that the X.Org X server incorrectly handled endianness conversion of certain X events. An attacker able to connect to an X server, either locally or remotely, could use this issue to crash the server, or possibly execute arbitrary code as an administrator. (CVE-2017-10971)
It was discovered that the X.Org X server incorrectly handled endianness conversion of certain X events. An attacker able to connect to an X server, either locally or remotely, could use this issue to possibly obtain sensitive information. (CVE-2017-10972)
Eric Sesterhenn discovered that the X.Org X server incorrectly compared MIT cookies. An attacker could possibly use this issue to perform a timing attack and recover the MIT cookie. (CVE-2017-2624)
The problem can be corrected by updating your system to the following package versions:
To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.
After a standard system update you need to reboot your computer to make all the necessary changes.
Vulmon