CVE-2026-82754

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Source

https://cve.org/CVERecord?id=CVE-2026-82754

Import Source

https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-82754.json

JSON Data

https://api.osv.dev/v1/vulns/CVE-2026-82754

Aliases

EEF-CVE-2026-82754
GHSA-wwxg-h779-3wf4

Published

2026-09-07T22:23:56Z

Modified

2026-09-09T03:47:29Z

Severity

6.3 (Medium) CVSS_V4 - CVSS: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 Calculator

Summary

ash_authentication_oauth2_server aliases every protocol endpoint under /.well-known, bypassing path-scoped controls

Details

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.

Database specific

{
    "cna_assigner": "EEF",
    "cwe_ids": [
        "CWE-424"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/82xxx/CVE-2026-82754.json",
    "unresolved_ranges": [
        {
            "extracted_events": [
                {
                    "introduced": "855b578037c5ded18e8a6e60f42e56bde4905fae"
                },
                {
                    "fixed": "a72972d7ed3eb74c05dfa0653a258ef14454459a"
                }
            ],
            "source": "AFFECTED_FIELD"
        }
    ]
}

References

Affected packages

Git / github.com/ash-project/ash_authentication_oauth2_server

Affected ranges

Type

GIT

Repo

https://github.com/ash-project/ash_authentication_oauth2_server

Events

Introduced

a4d8c361f710e5a050a1cf4834c9fa6c8f3dbd01

Fixed

15bde4311e31c925a428f34c02b283307619e2a2

Fixed

a72972d7ed3eb74c05dfa0653a258ef14454459a

Database specific

Show details

{
    "extracted_events": [
        {
            "introduced": "0.1.0"
        },
        {
            "fixed": "0.3.1"
        }
    ],
    "source": [
        "DESCRIPTION",
        "REFERENCES"
    ]
}

Affected versions

v0.*

v0.1.0

v0.1.1

v0.1.2

v0.1.3

v0.2.0

v0.2.1

v0.2.2

v0.3.0

Database specific

source

"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-82754.json"