Thunderbird could be made to crash or run programs as your login if it opened a specially crafted file.
Jesse Ruderman, Andreas Gal, Nils, Brian Hackett, and Igor Bukanov discovered several memory issues in the browser engine. An attacker could exploit these to crash THunderbird or possibly run arbitrary code as the user invoking the program. (CVE-2010-3776, CVE-2010-3777, CVE-2010-3778)
9 December 2010
A security issue affects these releases of Ubuntu and its derivatives:
Thunderbird could be made to crash or run programs as your login if it opened a specially crafted file.
Jesse Ruderman, Andreas Gal, Nils, Brian Hackett, and Igor Bukanov discovered several memory issues in the browser engine. An attacker could exploit these to crash THunderbird or possibly run arbitrary code as the user invoking the program. (CVE-2010-3776, CVE-2010-3777, CVE-2010-3778)
Marc Schoenefeld and Christoph Diehl discovered several problems when handling downloadable fonts. The new OTS font sanitizing library was added to mitigate these issues. (CVE-2010-3768)
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.
After a standard system update you need to restart Thunderbird to make all the necessary changes.