=========================================================================Ubuntu Security Notice USN-1130-1
May 10, 2011
A security issue affects these releases of Ubuntu and its derivatives:
- Ubuntu 11.04
- Ubuntu 10.10
- Ubuntu 10.04 LTS
Exim could be made to run arbitrary code under some conditions.
- exim4: Exim mail transfer agent
It was discovered that the Exim daemon did not correctly handle format
strings in DKIM headers. An unauthenticated remote attacker could send
specially crafted email to run arbitrary code as the Exim user. The
default compiler options for affected releases reduces the vulnerability
to a denial of service under most conditions.
The problem can be corrected by updating your system to the following