CVE-2026-79603

MEDIUMPre-NVD 4.34.3—
EchelonGraph scoreHIGH confidence

Score 4.3 from GitHub Security Advisory published 2026-09-08. CISA-ADP (Vulnrichment) CVSS v3.1 baseline 4.3; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cisa-adp, epss, ghsa
Trending — 3 sources updated this week
4.3EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 4.3Exploit: None knownExposed: 0

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

x86 PV guests can free memory pages while still keeping a stale TLB entry pointing to them. A TLB flush is only issued by Xen (if needed) when the page is re-used. Since it's possible for the page to be scrubbed ahead of the TLB flush, there's a window where a PV guest can modify an already scrubbed page.

CVSS v3
4.3
EG Score
4.3(high)
EG Risk
19(Track)
EG Risk 19/100SSVC: 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
Severity43% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
14%
KEV
Not listed

Published

September 8, 2026

Last Modified

September 8, 2026

Advisory Details (1)

Auto-updated Sep 8, 2026
No patch confirmed yet.
generic

XSA-511 - Xen Security Advisories

https://xenbits.xenproject.org/xsa/advisory-511.html

Vendor Advisories for CVE-2026-79603(1)

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

Affected Packages

(3 across 3 ecosystems)
Debian:12(1)
PackageVulnerable rangeFixed inDependents
xen4.17.1+2-gb773c48e36-1 ... 4.20.3+127-gc42374a105-1 (25 versions)——
Debian:13(1)
PackageVulnerable rangeFixed inDependents
xen4.20.0+68-g35cb38b222-1 ... 4.20.3+127-gc42374a105-1 (8 versions)——
Debian:14(1)
PackageVulnerable rangeFixed inDependents
xen4.20.0+68-g35cb38b222-1, 4.20.2+37-g61ff35323e-1, 4.20.2+7-g1badcf5035-1, 4.20.2+7-g1badcf5035-2, 4.20.3+127-gc42374a105-1——

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 18× in last 7d / 33× 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 03:07 UTCEG score recompute
  2. 2026-09-19 03:07 UTCGHSA enrichment
  3. 2026-09-18 19:28 UTCEPSS rescore
  4. 2026-09-18 02:41 UTCEG score recompute
  5. 2026-09-18 02:41 UTCGHSA enrichment
  6. 2026-09-17 02:17 UTCEG score recompute
  7. 2026-09-17 02:17 UTCGHSA enrichment
  8. 2026-09-16 14:08 UTCEPSS rescore
  9. 2026-09-16 05:15 UTCEPSS rescore
  10. 2026-09-16 01:53 UTCEG score recompute
  11. 2026-09-16 01:53 UTCGHSA enrichment
  12. 2026-09-15 03:12 UTCEPSS rescore
  13. 2026-09-15 03:12 UTCEPSS rescore
  14. 2026-09-15 01:28 UTCGHSA enrichment
  15. 2026-09-14 01:04 UTCEG score recompute
  16. 2026-09-14 01:04 UTCGHSA enrichment
  17. 2026-09-13 00:39 UTCEG score recompute
  18. 2026-09-13 00:39 UTCGHSA enrichment
  19. 2026-09-12 00:14 UTCEG score recompute
  20. 2026-09-12 00:14 UTCGHSA enrichment
  21. 2026-09-11 14:53 UTCEPSS rescore
  22. 2026-09-11 14:53 UTCEPSS rescore
  23. 2026-09-10 23:50 UTCEG score recompute
  24. 2026-09-10 23:50 UTCGHSA enrichment
  25. 2026-09-09 23:12 UTCGHSA enrichment
Show 8 more
  1. 2026-09-08 19:50 UTCGHSA enrichment
  2. 2026-09-08 18:14 UTCEG score recompute
  3. 2026-09-08 18:14 UTCGHSA enrichment
  4. 2026-09-08 13:50 UTCEG score recompute▲ 4.30
  5. 2026-09-08 13:49 UTCMITRE cvelistV5CVSS v3 → 4.3 · severity → MEDIUM
  6. 2026-09-08 13:25 UTCNVD update
  7. 2026-09-08 12:26 UTCEG score recompute
  8. 2026-09-08 12:24 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-79603?
CVE-2026-79603 is a medium vulnerability published on September 8, 2026. x86 PV guests can free memory pages while still keeping a stale TLB entry pointing to them. A TLB flush is only issued by Xen (if needed) when the page is re-used. Since it's possible for the page to be scrubbed ahead of the TLB flush, there's a window where a PV guest can modify an already…
When was CVE-2026-79603 disclosed?
CVE-2026-79603 was first published in the National Vulnerability Database on September 8, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-79603 actively exploited?
CVE-2026-79603 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 85.7% of all scored CVEs.
What is the CVSS score of CVE-2026-79603?
CVE-2026-79603 has a CVSS v3.1 base score of 4.3 (CISA-ADP / Vulnrichment enrichment; NVD's own analysis pending).
How do I remediate CVE-2026-79603?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-79603, 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

See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-79603

Explore →

Is Your Infrastructure Affected by CVE-2026-79603?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Start Free Scan →Browse All CVEs