An attacker that holds an OAuth2 token granting only part of the required scopes can authenticate, because when more than one scope is required in the configuration, the remote token validation paths accept a token that carries only one of them, while the local token validation path correctly requires all of them. The configured authorization policy is not enforced, so a token that was granted only part of the required permissions is accepted where it should have been rejected. Use local token validation where tokens can be validated locally. Update to non-vulnerable version. No publicly available exploits are known.
CVE-2026-40205
MEDIUMPre-NVD 5.95.9—Trending — 4 sources updated this week
EchelonGraph scoreHIGH confidence
Score 5.9 from GitHub Security Advisory published 2026-08-28. a secondary CVSS source baseline 5.9; sources differ by 0.0.
Triggered by: GitHub Security Advisory CVSS
Sources: ghsa, secondary
5.9EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
- Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 5.9Exploit: None knownExposed: 0
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 5.9
- EG Score
- 5.9(high)
- EG Risk
- 27(Track)EG Risk 27/100SSVC: 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 computedSeverity59% × 45%Exploitation0% × 40%Automatability0% × 15%Action: Routine — remediate on your standard cadence. - EPSS PROB
- 0%
- EPSS %ILE
- 8%
- KEV
- Not listed
Published
August 28, 2026
Last Modified
August 28, 2026
Advisory Details (1)
Auto-updated Aug 28, 2026No patch confirmed yet.
Vendor Advisories for CVE-2026-40205(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 9× in last 7d / 9× 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.
- 2026-08-30 01:22 UTCEPSS rescore
- 2026-08-29 14:54 UTCGHSA enrichment
- 2026-08-28 16:36 UTCEG score recompute
- 2026-08-28 16:36 UTCGHSA enrichment
- 2026-08-28 15:39 UTCEG score recompute
- 2026-08-28 15:38 UTCGHSA enrichment
- 2026-08-28 12:23 UTCEG score recompute
- 2026-08-28 11:25 UTCEG score recompute
- 2026-08-28 11:19 UTCMITRE cvelistV5first tracked
Related CVEs(same CWE)
Same CWE
10 shownCWE-287
Frequently asked(5)
What is CVE-2026-40205?
CVE-2026-40205 is a medium vulnerability published on August 28, 2026. An attacker that holds an OAuth2 token granting only part of the required scopes can authenticate, because when more than one scope is required in the configuration, the remote token validation paths accept a token that carries only one of them, while the local token validation path correctly…
When was CVE-2026-40205 disclosed?
CVE-2026-40205 was first published in the National Vulnerability Database on August 28, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-40205 actively exploited?
CVE-2026-40205 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 92.5% of all scored CVEs.
What is the CVSS score of CVE-2026-40205?
CVE-2026-40205 has a CVSS v3 base score of 5.9 (NVD).
How do I remediate CVE-2026-40205?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-40205, 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
Explore the affected products and dependency analysis for CVE-2026-40205
Is Your Infrastructure Affected by CVE-2026-40205?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.