CVE-2026-86533
Revoked session accepted because the session jti is never checked in AshAuthentication and AshAuthentication Phoenix
- State
- Published
- Severity
- 9.1 Critical
- Published
- Sep 17, 2026
- Updated
- Sep 17, 2026
- Reserved
- Sep 11, 2026
Description
Insufficient Session Expiration vulnerability in team-alembic AshAuthentication and AshAuthentication Phoenix allows a revoked session to remain fully authenticated.
A resource configured with session_identifier :jti and require_token_presence_for_authentication? disabled stores its session value as <jti>:<subject>. The jti is there so that signing out can revoke that one session. Neither reader consults it: AshAuthentication.Plug.Helpers.authenticate_resource_from_session/4 and AshAuthentication.Phoenix.LiveSession.on_mount/4 both split the value with split_identifier/2, discard the jti and pass the bare subject to AshAuthentication.subject_to_user/3, which reloads the record. The token-presence branch of each function does check its token, calling AshAuthentication.TokenResource.Actions.get_token/3 with the jti and the purpose user. Because the revocation record is never read, neither its revoked state nor its expiry constrains the session, so a session captured before sign-out keeps working.
This issue affects ash_authentication: from 4.9.1 before 4.15.0 and from 5.0.0-rc.0 before 5.0.0-rc.14; ash_authentication_phoenix: from 2.10.0 before 2.17.4 and from 3.0.0-rc.0 before 3.0.0-rc.11.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 4.0 | 9.1 Critical | CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N | EEF |
Weaknesses
- CWE-613 Insufficient Session Expiration
Affected Products
| Product | Versions |
|---|---|
ash_authenticationteam-alembic |
|
ash_authenticationteam-alembic |
|
ash_authentication_phoenixteam-alembic |
|
ash_authentication_phoenixteam-alembic |
|
References
- https://github.com/team-alembic/ash_authentication_phoenix/security/advisories/GHSA-m6x4-4gvp-xwjrvendor-advisoryrelated
- EEF CNA record for CVE-2026-86533related
- OSV record EEF-CVE-2026-86533related
- https://github.com/team-alembic/ash_authentication/security/advisories/GHSA-w374-hvrx-66hgrelatedvendor-advisory
- Introducing commit fcaeb73 in team-alembic/ash_authenticationrelated
- Fix commit a3f49f7 in team-alembic/ash_authenticationpatch
- Fix commit e28e911 in team-alembic/ash_authenticationpatch
- Introducing commit a3253fb in team-alembic/ash_authentication_phoenixrelated
- Introducing commit 0135217 in team-alembic/ash_authentication_phoenixrelated
- Fix commit f7ab005 in team-alembic/ash_authentication_phoenixpatch
Every record here comes from the CVE Program’s CVE List. © 1999–2026 The MITRE Corporation. CVE is a registered trademark of The MITRE Corporation. The records are reproduced under the CVE Program terms of use.