Several security issues were fixed in libXfont.
It was discovered that libXfont incorrectly handled certain patterns in PatternMatch. A local attacker could use this issue to cause libXfont to crash, resulting in a denial of service, or possibly obtain sensitive information. (CVE-2017-13720)
10 October 2017
A security issue affects these releases of Ubuntu and its derivatives:
Several security issues were fixed in libXfont.
It was discovered that libXfont incorrectly handled certain patterns in PatternMatch. A local attacker could use this issue to cause libXfont to crash, resulting in a denial of service, or possibly obtain sensitive information. (CVE-2017-13720)
It was discovered that libXfont incorrectly handled certain malformed PCF files. A local attacker could use this issue to cause libXfont to crash, resulting in a denial of service, or possibly obtain sensitive information. (CVE-2017-13722)
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.