Vulnerability record · CVE-2012-3494 · published 23 November 2012
CVE-2012-3494: Citrix xenserver permissions and access controls vulnerability
Citrix · Xenserver
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.
Description
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.
AV:L/AC:L/Au:N/C:N/I:N/A:P
Affected products
2 vulnerable configurations from NVD's CPE data, grouped by vendor and product.
References
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Related vulnerabilities
Same products first, then exploited flaws of the same weakness class.
Source: NIST National Vulnerability Database (record CVE-2012-3494), CISA KEV, FIRST EPSS (scores of 2026-10-05). This page is refreshed as NVD updates the record.