CVE-2026-79608 (GCVE-0-2026-79608)

Vulnerability from cvelistv5 – Published: 2026-10-13 15:44 – Updated: 2026-10-20 17:36
VLAI
Title
x86/AMD: ineffectual Zenbleed workaround
Summary
The workaround for XSA-433 (Zenbleed, CVE-2023-20593) was later re-worked to better integrate with other manipulations of the same MSR. In this rework an inverted conditional was introduced, resulting in the workaround to not be applied when needed and vice versa. For more details, see: http://xenbits.xen.org/xsa/advisory-433.html
Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-20 17:36 UTC
CWE
  • CWE-670 - Always-Incorrect Control Flow Implementation
Assigner
XEN CNA under the mitre root
CNA scorecard D 56/100 over 48 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Xen Xen Unknown: consult Xen advisory XSA-515
guessed Create a notification for this product.
Date Public
2026-10-13 12:00
Credits
This issue was discovered by Sashiko + Opus 5.0 and diagnosed as a security issue by George Dunlap.
Show details on NVD website
To clipboard 

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