The drive_init function in QEMU 0.9.1 determines the format of a raw disk image based on the header, which allows local guest users to read arbitrary files on the host by modifying the header to identify a different format, which is used when the guest is restarted.
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A11021
https://exchange.xforce.ibmcloud.com/vulnerabilities/42268
http://www.ubuntu.com/usn/usn-776-1
http://www.securityfocus.com/bid/29101
http://www.redhat.com/support/errata/RHSA-2008-0194.html
http://www.novell.com/linux/security/advisories/2008_13_sr.html
http://www.mandriva.com/security/advisories?name=MDVSA-2008:162
http://svn.savannah.gnu.org/viewvc/?view=rev&root=qemu&revision=4277
http://secunia.com/advisories/35062
http://secunia.com/advisories/30717
http://secunia.com/advisories/30111