Gentoo Linux Security Advisory 201407-3 - Multiple vulnerabilities have been found in Xen, the worst of which could lead to arbitrary code execution. Versions less than 4.3.2-r4 are affected.
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Ubuntu Security Notice 2092-1 - Asias He discovered that QEMU incorrectly handled SCSI controllers with more than 256 attached devices. A local user could possibly use this flaw to elevate privileges. It was discovered that QEMU incorrectly handled Xen disks. A local guest could possibly use this flaw to consume resources, resulting in a denial of service. This issue only affected Ubuntu 12.10 and Ubuntu 13.10. Various other issues were also addressed.
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