Wietse Venema discovered that Postfix leaked internal file descriptors when executing non-Postfix commands. A local attacker could exploit this to cause Postfix to run out of descriptors, leading to a denial of service.
The problem can be corrected by updating your system to the following package versions:
10 September 2008
A security issue affects these releases of Ubuntu and its derivatives:
Wietse Venema discovered that Postfix leaked internal file descriptors when executing non-Postfix commands. A local attacker could exploit this to cause Postfix to run out of descriptors, leading to a denial of service.
The problem can be corrected by updating your system to the following package versions:
To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.
In general, a standard system upgrade is sufficient to effect the necessary changes.