Several local vulnerabilities have been discovered in the Xen hypervisor packages which may lead to the execution of arbitrary code. The Common Vulnerabilities and Exposures project identifies the following problems:
By use of a specially crafted grub configuration file a domU user may be able to execute arbitrary code upon the dom0 when pygrub is being used.
Multiple heap-based buffer overflows in the Cirrus VGA extension,
provided by QEMU, may allow local users to execute arbitrary code
via bitblt
heap overflow.
For the stable distribution (etch), these problems have been fixed in version 3.0.3-0-3.
For the unstable distribution (sid), these problems will be fixed soon.
We recommend that you upgrade your xen-utils package.
MD5 checksums of the listed files are available in the original advisory.