x86/AMD: ineffectual Zenbleed workaround (Xen Xen)
At a glance
- Source
- NVD
- EPSS
- EPSS 0.35 % · percentile 29 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- XEN
- NVD status
- Awaiting Analysis
Description
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
Weaknesses (CWE)
- CWE-670 — Always-Incorrect Control Flow Implementation
References
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | CRITICAL 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H | CISA-ADP |
| CVSS 3.1 | CRITICAL 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H | NVD · 134c704f-9b21-4f2e-91b3-4a467353bcc0 (Secondary) |
European references
- ENISA EUVD · EUVD-2026-98824
- GCVE · GCVE-0-2026-79608
CERT-FR advisories
- CERTFR-2026-AVI-1302 — Multiples vulnérabilités dans Xen · cert.ssi.gouv.fr
Affected products
| Product | Versions |
|---|---|
| Xen · Xen | unknown consult Xen advisory XSA-515 |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| CERT-FR (ANSSI) | Licence Ouverte / Etalab 2.0 |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |