CVE-2026-80921

HIGHPre-NVD 8.88.8
EchelonGraph scoreHIGH confidence

Score 8.8 from GitHub Security Advisory (severity: HIGH) published 2026-09-09. a secondary CVSS source baseline 8.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 4 sources updated this week
8.8EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 8.8Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

In the Linux kernel, the following vulnerability has been resolved:

KVM: s390: vsie: zero stale crypto bits

When shadowing crypto access bits from a format0 apcb (crycb 0 or 1), the bits 64..255 are unchanged from whatever is in the vsie page in the crycb and thus in the apcb. This gives a nested guest potential access to a device no longer available. Zero out the remaining bits.

CVSS v3
8.8
EG Score
8.8(high)
EG Risk
44(Track)
EG Risk 44/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity88% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
3%
KEV
Not listed

Published

September 9, 2026

Last Modified

September 10, 2026

Advisory Details (9)

Auto-updated Sep 10, 2026
No patch confirmed yet.
generic

KVM: s390: vsie: zero stale crypto bits - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/34d5b5b646c91cfb9338d7a12c955a70ffb8c66b
generic

KVM: s390: vsie: zero stale crypto bits - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/29b4f7bc2991313bd3e6f6fb8fdf1b173f086dd6
generic

KVM: s390: vsie: zero stale crypto bits - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/d4bcd2df6d0d2af916b4fe1a533958778ea7c45b
generic

KVM: s390: vsie: zero stale crypto bits - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/935eeba276012916c76243e5cbb843efd8fdb75d
generic

KVM: s390: vsie: zero stale crypto bits - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/7d23489f51109e3ebba5b5db8c5f0185af7b7fdf
generic

KVM: s390: vsie: zero stale crypto bits - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/087c19cc60a8caa1a08e1e434c8be2caf6c27733
generic

KVM: s390: vsie: zero stale crypto bits - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/f6079dca67eccb5eabef9f72437948c66dc5131f
generic

KVM: s390: vsie: zero stale crypto bits - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/59d51550b5cb916bda037673a721a404b3b47a0d
generic

KVM: s390: vsie: zero stale crypto bits - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/d110b3297f11ef227098b8a82ade2d5f123b7d2f

Vendor Advisories for CVE-2026-80921(2)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Data Freshness Timeline

(refreshed 38× in last 7d / 55× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-09-19 10:06 UTCVendor advisory
  2. 2026-09-19 10:06 UTCGHSA enrichment
  3. 2026-09-18 21:56 UTCEG score recompute
  4. 2026-09-18 21:56 UTCVendor advisory
  5. 2026-09-18 21:56 UTCGHSA enrichment
  6. 2026-09-18 19:28 UTCEPSS rescore
  7. 2026-09-18 09:46 UTCVendor advisory
  8. 2026-09-18 09:46 UTCGHSA enrichment
  9. 2026-09-17 21:35 UTCEG score recompute
  10. 2026-09-17 21:35 UTCVendor advisory
  11. 2026-09-17 21:35 UTCGHSA enrichment
  12. 2026-09-17 09:24 UTCVendor advisory
  13. 2026-09-17 09:24 UTCGHSA enrichment
  14. 2026-09-16 21:13 UTCEG score recompute
  15. 2026-09-16 21:13 UTCVendor advisory
  16. 2026-09-16 21:13 UTCGHSA enrichment
  17. 2026-09-16 14:08 UTCEPSS rescore
  18. 2026-09-16 09:01 UTCEG score recompute
  19. 2026-09-16 09:01 UTCVendor advisory
  20. 2026-09-16 09:01 UTCGHSA enrichment
  21. 2026-09-16 05:15 UTCEPSS rescore
  22. 2026-09-15 20:50 UTCVendor advisory
  23. 2026-09-15 20:50 UTCGHSA enrichment
  24. 2026-09-15 08:23 UTCEG score recompute
  25. 2026-09-15 08:23 UTCVendor advisory
Show 30 more
  1. 2026-09-15 08:23 UTCGHSA enrichment
  2. 2026-09-15 03:12 UTCEPSS rescore
  3. 2026-09-15 03:12 UTCEPSS rescore
  4. 2026-09-14 20:12 UTCVendor advisory
  5. 2026-09-14 20:12 UTCGHSA enrichment
  6. 2026-09-14 08:01 UTCVendor advisory
  7. 2026-09-14 08:01 UTCGHSA enrichment
  8. 2026-09-13 19:51 UTCVendor advisory
  9. 2026-09-13 19:51 UTCGHSA enrichment
  10. 2026-09-13 07:40 UTCVendor advisory
  11. 2026-09-13 07:40 UTCGHSA enrichment
  12. 2026-09-12 19:30 UTCVendor advisory
  13. 2026-09-12 19:30 UTCGHSA enrichment
  14. 2026-09-12 07:19 UTCVendor advisory
  15. 2026-09-12 07:19 UTCGHSA enrichment
  16. 2026-09-11 19:08 UTCEG score recompute
  17. 2026-09-11 19:08 UTCVendor advisory
  18. 2026-09-11 19:08 UTCGHSA enrichment
  19. 2026-09-11 14:53 UTCEPSS rescore
  20. 2026-09-11 14:53 UTCEPSS rescore
  21. 2026-09-11 06:57 UTCGHSA enrichment
  22. 2026-09-10 18:46 UTCGHSA enrichment
  23. 2026-09-10 06:35 UTCEG score recompute
  24. 2026-09-10 06:35 UTCGHSA enrichment
  25. 2026-09-10 05:55 UTCEG score recompute 8.80
  26. 2026-09-10 05:55 UTCGHSA enrichment
  27. 2026-09-10 05:54 UTCMITRE cvelistV5CVSS v3 → 8.8 · severity → HIGH
  28. 2026-09-09 17:27 UTCNVD update
  29. 2026-09-09 16:29 UTCEG score recompute
  30. 2026-09-09 16:25 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-80921?
CVE-2026-80921 is a high vulnerability published on September 9, 2026. In the Linux kernel, the following vulnerability has been resolved: KVM: s390: vsie: zero stale crypto bits When shadowing crypto access bits from a format0 apcb (crycb 0 or 1), the bits 64..255 are unchanged from whatever is in the vsie page in the crycb and thus in the apcb. This gives a nested…
When was CVE-2026-80921 disclosed?
CVE-2026-80921 was first published in the National Vulnerability Database on September 9, 2026, with the most recent update on September 10, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-80921 actively exploited?
CVE-2026-80921 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 97.4% of all scored CVEs.
What is the CVSS score of CVE-2026-80921?
CVE-2026-80921 has a CVSS v3 base score of 8.8 (NVD).
How do I remediate CVE-2026-80921?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-80921, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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