CVE-2026-86533 PUBLISHED

Revoked session accepted because the session jti is never checked in AshAuthentication and AshAuthentication Phoenix

Assigner: EEF
Reserved: 11.09.2026 Published: 17.09.2026 Updated: 17.09.2026

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.

Metrics

CVSS Vector: 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
CVSS Score: 9.1

Product Status

Vendor team-alembic
Product ash_authentication
Versions Default: unaffected
  • affected from 4.9.1 to 4.15.0 (excl.)
  • affected from 5.0.0-rc.0 to 5.0.0-rc.14 (excl.)
Vendor team-alembic
Product ash_authentication
Versions Default: unaffected
  • affected from fcaeb73f76f8f2e9aef8bf637690d2a20dd97596 to * (excl.)
Vendor team-alembic
Product ash_authentication_phoenix
Versions Default: unaffected
  • affected from 2.10.0 to 2.17.4 (excl.)
  • affected from 3.0.0-rc.0 to 3.0.0-rc.11 (excl.)
Vendor team-alembic
Product ash_authentication_phoenix
Versions Default: unaffected
  • affected from a3253fb4fc7145aeb403537af1c24d3a8d51ffb1 to * (excl.)
  • affected from 0135217e34e621dac79ae3d9559aeee49304b0aa to * (excl.)

Credits

  • Peter Ullrich reporter
  • Jonatan Männchen / EEF analyst
  • James Harton remediation developer

References

Problem Types

  • CWE-613 Insufficient Session Expiration CWE

Impacts

  • CAPEC-60 Reusing Session IDs (aka Session Replay)