It was discovered that libicu did not correctly handle certain invalid encoded data. If a user or automated system were tricked into processing specially crafted data with applications linked against libicu, certain content filters could be bypassed.
The problem can be corrected by updating your system to the following package versions:
26 March 2009
A security issue affects these releases of Ubuntu and its derivatives:
It was discovered that libicu did not correctly handle certain invalid encoded data. If a user or automated system were tricked into processing specially crafted data with applications linked against libicu, certain content filters could be bypassed.
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 upgrade you need to restart applications linked against libicu, such as OpenOffice.org, to effect the necessary changes.