Canonical published details about ClamAV vulnerabilities, in a security notice, for its Ubuntu 12.10, Ubuntu 12.04 LTS, Ubuntu 11.10, and Ubuntu 10.04 LTS operating systems.
According to Canonical, several security issues were fixed in ClamAV.
Felix Groebert, Mateusz Jurczyk and Gynvael Coldwind discovered multiple security issues with ClamAV. An attacker could use these issues to cause ClamAV to crash, resulting in a denial of service, or possibly execute arbitrary code.
For a more detailed description of the security problems, you can visit Canonical's security notification.
The security flaws can be fixed if you upgrade your system(s) to the latest libclamav6, clamav and clamav-daemon package, specific to each distribution. To apply the update, run the Update Manager application.
In general, a standard system update will make all the necessary changes. A system restart will not be necessary to implement the changes.