CVE-2012-3494: Citrix Xenserver

Low severity, CVSS 2.1. EPSS: 0.4% chance of exploitation in the next 30 days.

The set_debugreg hypercall in include/asm-x86/debugreg.h in Xen 4.0, 4.1, and 4.2, and Citrix XenServer 6.0.2 and earlier, when running on x86-64 systems, allows local OS guest users to cause a denial of service (host crash) by writing to the reserved bits of the DR7 debug control register.

Affected products

• Citrix Xenserver: up to and including 6.0.2
• Xen Xen: version 4.0.0 only; version 4.1.0 only; version 4.2.0 only

Published 2012-11-23. Last modified 2026-06-16.