CVE-2026-82755

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 70% 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.

Use of Cache Containing Sensitive Information vulnerability in ash-project ash_authentication_oauth2_server allows a shared HTTP cache to serve one tenant's OAuth discovery metadata to another tenant's clients.

The RFC 8414 and RFC 9728 metadata endpoints in AshAuthentication.Phoenix.Oauth2Server.ProtocolRouter return tenant-specific values (issuer, authorization_endpoint, token_endpoint, jwks_uri) when a tenant is set, but sent them with Cache-Control: public, max-age=3600 and no Vary. When the tenant is derived from something other than the URL (a header or the Host) and a shared cache sits in front, the cache key is the URL alone, so a stored response for one tenant is served to another for up to an hour. Affected clients may then send authorization codes and secrets to the wrong tenant's token endpoint and validate tokens against the wrong keys.

This issue affects ash_authentication_oauth2_server: from 0.1.3 before 0.3.1.

CVSS v3
6.3
EG Score
6.3(medium)
EG Risk
28(Track)
EG Risk 28/100SSVC: 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
30%
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 768d87f70e4e (ash-project/ash_authentication_oauth2_server)

Patch available: ash-project/ash_authentication_oauth2_server v0.3.1 (contains commit 768d87f70e4e)

https://github.com/ash-project/ash_authentication_oauth2_server/commit/768d87f70e4e97ae1d2bf1606b5bf3f4d03f24a1
generic

OSV - Open Source Vulnerabilities

https://osv.dev/vulnerability/EEF-CVE-2026-82755
generic

CVE-2026-82755

https://cna.erlef.org/cves/CVE-2026-82755.html
github Patch Available

Tenant-specific OAuth metadata is publicly cacheable, enabling cross-tenant confusion 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-crqf-7m54-4hgc

Affected Packages

(1 across 1 ecosystem)
Hex(1)
PackageVulnerable rangeFixed inDependents
ash_authentication_oauth2_server0.1.3, 0.2.0, 0.2.1, 0.2.2, 0.3.00.3.1—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 12× in last 7d / 23× 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. 2026-09-18 20:16 UTCEG score recompute
  2. 2026-09-18 19:28 UTCEPSS rescore
  3. 2026-09-17 22:01 UTCEG score recompute
  4. 2026-09-16 23:50 UTCEG score recompute
  5. 2026-09-16 14:08 UTCEPSS rescore
  6. 2026-09-16 05:15 UTCEPSS rescore
  7. 2026-09-15 03:28 UTCEG score recompute
  8. 2026-09-15 03:12 UTCEPSS rescore
  9. 2026-09-15 03:12 UTCEPSS rescore
  10. 2026-09-14 05:17 UTCEG score recompute
  11. 2026-09-13 07:06 UTCEG score recompute
  12. 2026-09-12 08:55 UTCEG score recompute
  13. 2026-09-11 14:53 UTCEPSS rescore
  14. 2026-09-11 14:53 UTCEPSS rescore
  15. 2026-09-11 10:43 UTCEG score recompute
  16. 2026-09-10 12:06 UTCEG score recompute
  17. 2026-09-09 13:54 UTCEG score recompute
  18. 2026-09-08 22:01 UTCEPSS rescore
  19. 2026-09-08 15:43 UTCEG score recompute
  20. 2026-09-08 14:47 UTCEG score recompute
  21. 2026-09-07 23:35 UTCEG score recompute
  22. 2026-09-07 22:32 UTCEG score recompute
  23. 2026-09-07 22:31 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-82755?
CVE-2026-82755 is a medium vulnerability published on September 7, 2026. Use of Cache Containing Sensitive Information vulnerability in ash-project ashauthenticationoauth2_server allows a shared HTTP cache to serve one tenant's OAuth discovery metadata to another tenant's clients. The RFC 8414 and RFC 9728 metadata endpoints in…
When was CVE-2026-82755 disclosed?
CVE-2026-82755 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-2026-82755 actively exploited?
CVE-2026-82755 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 69.5% of all scored CVEs.
What is the CVSS score of CVE-2026-82755?
CVE-2026-82755 has a CVSS v3 base score of 6.3 (NVD).
How do I remediate CVE-2026-82755?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-82755, 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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