Ubuntu Security Notice USN-1196-1
23rd August, 2011
A security issue affects these releases of Ubuntu and its derivatives:
- Ubuntu 11.04
- Ubuntu 10.10
- Ubuntu 10.04 LTS
An attacker could use eCryptfs to unmount arbitrary locations and cause a denial of service.
- ecryptfs-utils - ecryptfs cryptographic filesystem (utilities)
It was discovered that eCryptfs incorrectly handled permissions when
modifying the mtab file. A local attacker could use this flaw to manipulate
the mtab file, and possibly unmount arbitrary locations, leading to a
denial of service.
The problem can be corrected by updating your system to the following package version:
- Ubuntu 11.04:
- ecryptfs-utils 87-0ubuntu1.2
- Ubuntu 10.10:
- ecryptfs-utils 83-0ubuntu126.96.36.199.2
- Ubuntu 10.04 LTS:
- ecryptfs-utils 83-0ubuntu3.2.10.04.2
To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.
In general, a standard system update will make all the necessary changes.