CVE-2026-82754Network attack vector

Access-control bypass via aliased OAuth routes

Published Sep 7, 2026 · Updated Sep 8, 2026

Access control bypass in Ash Project ash_authentication_oauth2_server before 0.3.1 allows remote attackers to reach alternate OAuth routes. oauth2_server_protocol_routes/1 forwards the full ProtocolRouter under both /oauth and /.well-known after Phoenix strips each mount prefix. The alias is unconditional; impact requires path-scoped edge controls and permits unauthorized state-changing requests that those controls would block.

CVSS severity6.3
Medium
EPSS probability0.39%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Access control bypass in Ash Project ash_authentication_oauth2_server before 0.3.1 allows remote attackers to reach alternate OAuth routes. oauth2_server_protocol_routes/1 forwards the full ProtocolRouter under both /oauth and /.well-known after Phoenix strips each mount prefix. The alias is unconditional; impact requires path-scoped edge controls and permits unauthorized state-changing requests that those controls would block.

The record

CVE
CVE-2026-82754
Published
Sep 7, 2026
Updated
Sep 8, 2026
Vendor
Ash Project
Product
ash_authentication_oauth2_server
Classifications
CWE-424, CAPEC-554, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 7, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 8, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0.1.0 <0.3.1
  2. Affected versionversion=855b578037c5ded18e8a6e60f42e56bde4905fae <a72972d7ed3eb74c05dfa0653a258ef14454459a

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Ash Project · ash_authentication_oauth2_serverversion=0.1.0 <0.3.1; version=855b578037c5ded18e8a6e60f42e56bde4905fae <a72972d7ed3eb74c05dfa0653a258ef14454459a

Published CVSS scores

6.3Erlang Ecosystem Foundation CNACVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-424Improper Protection of Alternate Path
CAPEC-554Functionality Bypass
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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