Ubuntu Update for postfix vulnerabilities USN-642-1

Summary
Ubuntu Update for Linux kernel vulnerabilities USN-642-1
Solution
Please Install the Updated Packages.
Insight
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.
Affected
postfix vulnerabilities on Ubuntu 7.10 , Ubuntu 8.04 LTS