CVE-2026-82754

MEDIUMPre-NVD 6.36.3—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 6.3 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.4%, top 68% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, secondary
6.3EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 6.3Exploit: None knownExposed: 0

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

Improper Protection of Alternate Path vulnerability in ash-project ash_authentication_oauth2_server exposes the state-changing OAuth endpoints under an unintended URL prefix, bypassing controls scoped to the canonical prefix.

oauth2_server_protocol_routes/1 in AshAuthentication.Phoenix.Oauth2Server.Router forwards the same ProtocolRouter at both the /oauth prefix and the /.well-known prefix. Phoenix forward strips the matched prefix before dispatch, so the full route table answers under both mounts, and POST /register, POST /token, and POST /revoke are reachable as /.well-known/register, /.well-known/token, and /.well-known/revoke. Edge controls such as WAF rules, rate limits, or authentication exemptions written against the /oauth paths, or that allow-list /.well-known as unauthenticated, do not apply to the alias.

This issue affects ash_authentication_oauth2_server: from 0.1.0 before 0.3.1.

CVSS v3
6.3
EG Score
6.3(medium)
EG Risk
29(Track)
EG Risk 29/100SSVC: 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
Severity63% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
32%
KEV
Not listed

Published

September 7, 2026

Last Modified

September 8, 2026

Advisory Details (4)

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

commit a72972d7ed3e (ash-project/ash_authentication_oauth2_server)

Patch available: ash-project/ash_authentication_oauth2_server v0.3.1 (contains commit a72972d7ed3e)

https://github.com/ash-project/ash_authentication_oauth2_server/commit/a72972d7ed3eb74c05dfa0653a258ef14454459a
generic

OSV - Open Source Vulnerabilities

https://osv.dev/vulnerability/EEF-CVE-2026-82754
generic

CVE-2026-82754

https://cna.erlef.org/cves/CVE-2026-82754.html
github Patch Available

State-changing OAuth endpoints aliased under /.well-known bypass path-scoped controls in ash_authentication_oauth2_server · Advisory · ash-project/ash_authentication_oauth2_server · GitHub

https://github.com/ash-project/ash_authentication_oauth2_server/security/advisories/GHSA-wwxg-h779-3wf4

Affected Packages

(1 across 1 ecosystem)
Hex(1)
PackageVulnerable rangeFixed inDependents
ash_authentication_oauth2_server0.1.0 ... 0.3.0 (8 versions)0.3.1—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 13× in last 7d / 24× 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 02:30 UTCEG score recompute
  2. 2026-09-18 19:28 UTCEPSS rescore
  3. 2026-09-18 03:43 UTCEG score recompute
  4. 2026-09-17 04:57 UTCEG score recompute
  5. 2026-09-16 14:08 UTCEPSS rescore
  6. 2026-09-16 06:11 UTCEG score recompute
  7. 2026-09-16 05:15 UTCEPSS rescore
  8. 2026-09-15 07:24 UTCEG score recompute
  9. 2026-09-15 03:12 UTCEPSS rescore
  10. 2026-09-15 03:12 UTCEPSS rescore
  11. 2026-09-14 08:38 UTCEG score recompute
  12. 2026-09-13 09:52 UTCEG score recompute
  13. 2026-09-12 11:05 UTCEG score recompute
  14. 2026-09-11 14:53 UTCEPSS rescore
  15. 2026-09-11 14:53 UTCEPSS rescore
  16. 2026-09-11 12:03 UTCEG score recompute
  17. 2026-09-10 13:17 UTCEG score recompute
  18. 2026-09-09 14:31 UTCEG score recompute
  19. 2026-09-08 22:01 UTCEPSS rescore
  20. 2026-09-08 15:43 UTCEG score recompute
  21. 2026-09-08 14:47 UTCEG score recompute
  22. 2026-09-07 23:35 UTCEG score recompute
  23. 2026-09-07 22:32 UTCEG score recompute
  24. 2026-09-07 22:31 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-82754?
CVE-2026-82754 is a medium vulnerability published on September 7, 2026. Improper Protection of Alternate Path vulnerability in ash-project ashauthenticationoauth2_server exposes the state-changing OAuth endpoints under an unintended URL prefix, bypassing controls scoped to the canonical prefix. oauth2serverprotocol_routes/1 in…
When was CVE-2026-82754 disclosed?
CVE-2026-82754 was first published in the National Vulnerability Database on September 7, 2026, with the most recent update 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-2026-82754 actively exploited?
CVE-2026-82754 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 67.6% of all scored CVEs.
What is the CVSS score of CVE-2026-82754?
CVE-2026-82754 has a CVSS v3 base score of 6.3 (NVD).
How do I remediate CVE-2026-82754?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-82754, 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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