Not scored yet

CVE-2026-86533

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 : . 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.

What this means for your business

    What to do

    1. 1Ask your IT team or provider whether any of your systems use the affected product.
    2. 2If you do, follow the vendor's guidance. No patch reference has been published yet.

    Not sure if your company is exposed?

    Fastnexa’s certified penetration testers can check whether attackers could use this flaw, or others like it, against your websites, apps and network. The full test is free for our first 10 founding clients until 31 December 2026.

    Scoring

    CVSS
    Not yet scored
    CVSS v4
    9.1
    Weakness
    CWE-613
    Assigned by
    6b3ad84c-e1a6-4bf7-a703-f496b71e49db

    Dates

    Published
    2026-09-17
    Last modified
    2026-09-18
    Sources
    NVD

    References