CVE-2026-79611 (GCVE-0-2026-79611)
Vulnerability from cvelistv5
Published
2026-10-13 15:44
Modified
2026-10-20 17:31
Severity ?
5.5 (Medium) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Summary
For XSA-308 logic was introduced, as VMX VMEntry checks do not like the exact combination of state which occurs when #DB in intercepted, Single Stepping is active, and blocked by STI/MovSS is active, despite this being a legitimate state to be in. The resulting VMEntry failure is fatal to the guest. Sadly there is another special sub-case of the above, with branch tracing enabled. In that case the prior adjustment would still cause a VMentry failure, as before fatal to the guest.
References
Impacted products
Vendor Product Version
Xen Xen Create a notification for this product.
Show details on NVD website

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