This advisory also applies to the corresponding versions of Kubuntu, Edubuntu, and Xubuntu.
Details follow:
USN-603-1 fixed vulnerabilities in poppler. This update provides the corresponding updates for KWord, part of KOffice.
Original advisory details:
It was discovered that the poppler PDF library did not correctly handle certain malformed embedded fonts. If a user or an automated system were tricked into opening a malicious PDF, a remote attacker could execute arbitrary code with user privileges.
Solution: The problem can be corrected by upgrading your system to the following package versions:
Ubuntu 6.06 LTS: kword 1:1.5.0-0ubuntu9.4
Ubuntu 6.10: kword 1:1.5.2-0ubuntu2.4
Ubuntu 7.04: kword 1:1.6.2-0ubuntu1.3
Ubuntu 7.10: kword 1:1.6.3-0ubuntu5.2
After a standard system upgrade you need to restart KWord to effect the necessary changes.