CVE-2026-86544

HIGHPre-NVD 8.18.1—
EchelonGraph scoreHIGH confidence

Score 8.1 from GitHub Security Advisory (severity: HIGH) published 2026-09-08. the CNA's CVSS baseline 8.1; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cna:vulncheck, epss, ghsa
Trending — 3 sources updated this week
8.1EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 1%CVSS: 8.1Exploit: None knownExposed: 0

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

knowns versions before 0.30.0 contain an authorization bypass vulnerability where mutating code actions are incorrectly classified as read-only operations. Attackers with read-restricted sessions can exploit code.replace to modify permission configurations and escalate privileges on subsequent calls.

CVSS v3
8.1
EG Score
8.1(high)
EG Risk
37(Track)
EG Risk 37/100SSVC: 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
Severity81% × 45%
Exploitation1% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
1%
EPSS %ILE
46%
KEV
Not listed

Published

September 7, 2026

Last Modified

September 24, 2026

Advisory Details (6)

Auto-updated Sep 7, 2026
Patch available. Sources: github, github_commit, github_release.
generic

knowns before 0.30.0 Authorization Bypass via Misclassified Code Actions | Advisories | VulnCheck

https://www.vulncheck.com/advisories/knowns-before-0.30.0-authorization-bypass-via-misclassified-code-actions
github_release Patch Available

v0.30.0

Patch available: knowns-dev/knowns v0.30.0

https://github.com/knowns-dev/knowns/releases/tag/v0.30.0
github_commit

commit a2c98fc5c313 (knowns-dev/knowns)

Fix landed in knowns-dev/knowns commit a2c98fc5c313 — awaiting tagged release

https://github.com/knowns-dev/knowns/commit/a2c98fc5c313463576c9348beeec6a74ddd7333b
generic

knowns/internal/permissions/guard.go at v0.29.1 · knowns-dev/knowns · GitHub

https://github.com/knowns-dev/knowns/blob/v0.29.1/internal/permissions/guard.go#L44-L60
generic

knowns/internal/permissions/registry.go at v0.29.1 · knowns-dev/knowns · GitHub

https://github.com/knowns-dev/knowns/blob/v0.29.1/internal/permissions/registry.go#L99-L140
github Patch Available

MCP Permission Guard Bypass: code.replace (CapRead) Self-Grants Delete · Advisory · knowns-dev/knowns · GitHub

https://github.com/knowns-dev/knowns/security/advisories/GHSA-w323-3wpx-f7g5

Vendor Advisories for CVE-2026-86544(1)

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

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 27× in last 7d / 74× 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. 2026-09-25 02:37 UTCGHSA enrichment
  2. 2026-09-24 14:53 UTCEG score recompute
  3. 2026-09-24 14:53 UTCGHSA enrichment
  4. 2026-09-24 14:04 UTCEPSS rescore
  5. 2026-09-24 05:53 UTCGHSA enrichment
  6. 2026-09-23 18:10 UTCEG score recompute
  7. 2026-09-23 18:09 UTCGHSA enrichment
  8. 2026-09-23 17:54 UTCEPSS rescore
  9. 2026-09-23 06:26 UTCGHSA enrichment
  10. 2026-09-22 18:43 UTCEG score recompute
  11. 2026-09-22 18:43 UTCGHSA enrichment
  12. 2026-09-22 16:01 UTCEPSS rescore
  13. 2026-09-22 06:59 UTCEG score recompute
  14. 2026-09-22 06:59 UTCGHSA enrichment
  15. 2026-09-21 21:09 UTCEPSS rescore
  16. 2026-09-21 19:16 UTCGHSA enrichment
  17. 2026-09-21 07:33 UTCEG score recompute
  18. 2026-09-21 07:33 UTCGHSA enrichment
  19. 2026-09-20 20:16 UTCEPSS rescore
  20. 2026-09-20 19:50 UTCGHSA enrichment
  21. 2026-09-20 08:07 UTCGHSA enrichment
  22. 2026-09-19 19:43 UTCEG score recompute
  23. 2026-09-19 19:43 UTCGHSA enrichment
  24. 2026-09-19 07:59 UTCGHSA enrichment
  25. 2026-09-18 20:16 UTCEG score recompute
Show 49 more
  1. 2026-09-18 20:15 UTCGHSA enrichment
  2. 2026-09-18 19:28 UTCEPSS rescore
  3. 2026-09-18 08:29 UTCGHSA enrichment
  4. 2026-09-17 20:46 UTCEG score recompute
  5. 2026-09-17 20:46 UTCGHSA enrichment
  6. 2026-09-17 19:32 UTCEPSS rescore
  7. 2026-09-17 09:02 UTCGHSA enrichment
  8. 2026-09-16 21:18 UTCEG score recompute
  9. 2026-09-16 21:18 UTCGHSA enrichment
  10. 2026-09-16 14:09 UTCEPSS rescore
  11. 2026-09-16 08:58 UTCEG score recompute
  12. 2026-09-16 08:58 UTCGHSA enrichment
  13. 2026-09-16 05:15 UTCEPSS rescore
  14. 2026-09-15 21:10 UTCGHSA enrichment
  15. 2026-09-15 09:27 UTCEG score recompute
  16. 2026-09-15 09:27 UTCGHSA enrichment
  17. 2026-09-15 03:12 UTCEPSS rescore
  18. 2026-09-15 03:12 UTCEPSS rescore
  19. 2026-09-14 21:44 UTCGHSA enrichment
  20. 2026-09-14 10:00 UTCGHSA enrichment
  21. 2026-09-13 22:17 UTCEG score recompute
  22. 2026-09-13 22:17 UTCGHSA enrichment
  23. 2026-09-13 10:33 UTCGHSA enrichment
  24. 2026-09-12 22:48 UTCEG score recompute
  25. 2026-09-12 22:48 UTCGHSA enrichment
  26. 2026-09-12 11:05 UTCGHSA enrichment
  27. 2026-09-11 23:13 UTCEG score recompute
  28. 2026-09-11 23:13 UTCGHSA enrichment
  29. 2026-09-11 14:53 UTCEPSS rescore
  30. 2026-09-11 14:53 UTCEPSS rescore
  31. 2026-09-11 11:18 UTCEG score recompute
  32. 2026-09-11 11:18 UTCGHSA enrichment
  33. 2026-09-11 02:43 UTCGHSA enrichment
  34. 2026-09-10 15:00 UTCEG score recompute
  35. 2026-09-10 14:59 UTCGHSA enrichment
  36. 2026-09-10 03:14 UTCGHSA enrichment
  37. 2026-09-09 15:31 UTCEG score recompute
  38. 2026-09-09 15:31 UTCGHSA enrichment
  39. 2026-09-09 14:55 UTCEG score recompute
  40. 2026-09-09 14:55 UTCGHSA enrichment
  41. 2026-09-09 07:55 UTCEG score recompute
  42. 2026-09-09 07:55 UTCGHSA enrichment
  43. 2026-09-08 22:01 UTCEPSS rescore
  44. 2026-09-08 20:12 UTCGHSA enrichment
  45. 2026-09-08 11:19 UTCEG score recompute
  46. 2026-09-08 11:18 UTCGHSA enrichment
  47. 2026-09-07 23:35 UTCEG score recompute
  48. 2026-09-07 23:07 UTCEG score recompute
  49. 2026-09-07 23:06 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-86544?
CVE-2026-86544 is a high vulnerability published on September 7, 2026. knowns versions before 0.30.0 contain an authorization bypass vulnerability where mutating code actions are incorrectly classified as read-only operations. Attackers with read-restricted sessions can exploit code.replace to modify permission configurations and escalate privileges on subsequent…
When was CVE-2026-86544 disclosed?
CVE-2026-86544 was first published in the National Vulnerability Database on September 7, 2026, with the most recent update on September 24, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-86544 actively exploited?
CVE-2026-86544 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 1% probability of exploitation in the next 30 days, which ranks it in the top 54.4% of all scored CVEs.
What is the CVSS score of CVE-2026-86544?
CVE-2026-86544 has a CVSS v4.0 base score of 8.1 (CNA self-assessment; NVD's own analysis pending).
How do I remediate CVE-2026-86544?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-86544, 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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