CVE-2026-82754
NVD: 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. NVD: oauth2_server_protocol_routes/1 in AshAuthentication.Phoenix.Oauth2Server.Router forwards the same ProtocolRouter at both the /oauth prefix and the /.well-known prefix. NVD: 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.
6.3 Severity
MEDIUM EPSS
0.0039 (32) KEV
-
Source-published summary
NVD: 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. NVD: oauth2_server_protocol_routes/1 in AshAuthentication.Phoenix.Oauth2Server.Router forwards the same ProtocolRouter at both the /oauth prefix and the /.well-known prefix. NVD: 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.
Possible impact
This medium severity issue needs human triage to confirm exposure, affected versions, and vendor guidance for defensive exposure review.
Affected context
Affected product or version requires source confirmation.
Remediation / advisory
Remediation reference present; patch status requires confirmation in the linked advisory.
Why it matters
This medium severity issue needs human triage to confirm exposure, affected versions, and vendor guidance for defensive exposure review.; CVSS 6.3 (MEDIUM); EPSS percentile 32; not listed in KEV; Remediation reference present; patch status requires confirmation in the linked advisory; sources: NVD, OSV.
What to verify
Confirm affected product/version, vendor advisory, patch or mitigation, and exposure.
Exposure hint
exposure unknown
Impact tags
Urgency reasons
Source-derived note
Summary derived from NVD / OSV description; unsafe procedural detail is not shown.
Redaction metadata
- source summary used
- True
- fallback summary used
- False
- unsafe procedural detail present
- false
- raw source displayed
- false
- public summary redacted
- true
Remediation handoff
Public-safe static handoff for human/Codex remediation planning. Scan, patch, external execution, and auto remediation are disabled.
Safety note
This radar shows source-published defensive context only. Exploit procedures, exploit strings, scanner commands, and auto-remediation are not provided.