USN-3442-1: libXfont vulnerabilities

Ubuntu Security Notice USN-3442-1

10th October, 2017

libxfont, libxfont1, libxfont2 vulnerabilities

A security issue affects these releases of Ubuntu and its derivatives:

  • Ubuntu 17.04
  • Ubuntu 16.04 LTS
  • Ubuntu 14.04 LTS

Summary

Several security issues were fixed in libXfont.

Software description

  • libxfont - X11 font rasterisation library
  • libxfont1 - X11 font rasterisation library
  • libxfont2 - X11 font rasterisation library

Details

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)

Update instructions

The problem can be corrected by updating your system to the following package version:

Ubuntu 17.04:
libxfont1 1:1.5.2-4ubuntu0.1
libxfont2 1:2.0.1-3ubuntu0.1
Ubuntu 16.04 LTS:
libxfont1 1:1.5.1-1ubuntu0.16.04.3
libxfont2 1:2.0.1-3~ubuntu16.04.2
Ubuntu 14.04 LTS:
libxfont1 1:1.4.7-1ubuntu0.3

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.

References

CVE-2017-13720, CVE-2017-13722