USN-3500-1: libXfont vulnerability
Ubuntu Security Notice USN-3500-1
29th November, 2017
libxfont, libxfont1, libxfont2 vulnerability
A security issue affects these releases of Ubuntu and its
derivatives:
- Ubuntu 17.10
- Ubuntu 17.04
- Ubuntu 16.04 LTS
- Ubuntu 14.04 LTS
Summary
libXfont could be made to access arbitrary files, including special device
files.
Software description
- libxfont
– X11 font rasterisation library - libxfont1
– X11 font rasterisation library - libxfont2
– X11 font rasterisation library
Details
It was discovered that libXfont incorrectly followed symlinks when opening
font files. A local unprivileged user could use this issue to cause the X
server to access arbitrary files, including special device files.
Update instructions
The problem can be corrected by updating your system to the following
package version:
- Ubuntu 17.10:
-
libxfont1
1:1.5.2-4ubuntu1.1
-
libxfont2
1:2.0.1-3ubuntu1.1
- Ubuntu 17.04:
-
libxfont1
1:1.5.2-4ubuntu0.2
-
libxfont2
1:2.0.1-3ubuntu0.2
- Ubuntu 16.04 LTS:
-
libxfont1
1:1.5.1-1ubuntu0.16.04.4
-
libxfont2
1:2.0.1-3~ubuntu16.04.3
- Ubuntu 14.04 LTS:
-
libxfont1
1:1.4.7-1ubuntu0.4
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
Source: USN-3500-1: libXfont vulnerability
