USN-1196-1: eCryptfs vulnerability

23 August 2011

ecryptfs-utils vulnerability

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

  • Ubuntu 11.04
  • Ubuntu 10.10
  • Ubuntu 10.04 LTS

Summary

An attacker could use eCryptfs to unmount arbitrary locations and cause a denial of service.

Software Description

  • ecryptfs-utils - ecryptfs cryptographic filesystem (utilities)

Details

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.

Update instructions

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

Ubuntu 11.04
ecryptfs-utils - 87-0ubuntu1.2
Ubuntu 10.10
ecryptfs-utils - 83-0ubuntu3.2.10.10.2
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.

References