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.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| team-alembic | ash_authentication | 4.9.1 – < 4.15.0, 5.0.0-rc.0 – < 5.0.0-rc.14 | 4.15.0 |
| team-alembic | ash_authentication_phoenix | 2.10.0 – < 2.17.4, 3.0.0-rc.0 – < 3.0.0-rc.11 | 2.17.4 |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| Hex | ash_authentication | >= 4.9.1, < 4.15.0 · >= 5.0.0-rc.0, < 5.0.0-rc.14 | 4.15.0, 5.0.0-rc.14 | EEF-CVE-2026-86533 |
| Hex | ash_authentication_phoenix | >= 2.10.0, < 2.17.4 · >= 3.0.0-rc.0, < 3.0.0-rc.11 | 2.17.4, 3.0.0-rc.11 | EEF-CVE-2026-86533 |
References
- https://github.com/team-alembic/ash_authentication_phoenix/security/advisories/GHSA-m6x4-4gvp-xwjr vendor-advisory related
- EEF CNA record for CVE-2026-86533 related
- OSV record EEF-CVE-2026-86533 related
- https://github.com/team-alembic/ash_authentication/security/advisories/GHSA-w374-hvrx-66hg related vendor-advisory
- Introducing commit fcaeb73 in team-alembic/ash_authentication related
- Fix commit a3f49f7 in team-alembic/ash_authentication patch
- Fix commit e28e911 in team-alembic/ash_authentication patch
- Introducing commit a3253fb in team-alembic/ash_authentication_phoenix related
- Introducing commit 0135217 in team-alembic/ash_authentication_phoenix related
- Fix commit f7ab005 in team-alembic/ash_authentication_phoenix patch