The system could be made to crash under certain conditions.
Andrew Cooper of Citrix reported a Xen stack corruption in the Linux kernel. An unprivileged user in a 32bit PVOPS guest can cause the guest kernel to crash, or operate erroneously.
19 February 2013
A security issue affects these releases of Ubuntu and its derivatives:
The system could be made to crash under certain conditions.
Andrew Cooper of Citrix reported a Xen stack corruption in the Linux kernel. An unprivileged user in a 32bit PVOPS guest can cause the guest kernel to crash, or operate erroneously.
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 reboot your computer to make all the necessary changes.
Vulmon