Xen 3.0.3 - Authenticated Remote Code Execution via Crafted grub.conf File
pygrub (tools/pygrub/src/GrubConf.py) in Xen 3.0.3, when booting a guest domain, allows local users with elevated privileges in the guest domain to execute arbitrary commands in domain 0 via a crafted grub.conf file whose contents are used in exec statements.