CVE-2026-86533
Revoked session accepted because the session jti is never checked in AshAuthentication and AshAuthentication Phoenix
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.
INFO
Published Date :
Sept. 17, 2026, 2:17 p.m.
Last Modified :
Sept. 18, 2026, 6:16 p.m.
Remotely Exploit :
Yes !
Source :
6b3ad84c-e1a6-4bf7-a703-f496b71e49db
Affected Products
The following products are affected by CVE-2026-86533
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 4.0 | CRITICAL | 6b3ad84c-e1a6-4bf7-a703-f496b71e49db | ||||
| CVSS 4.0 | CRITICAL | 6b3ad84c-e1a6-4bf7-a703-f496b71e49db |
Solution
- Update ash_authentication to version 4.15.0 or later.
- Update ash_authentication to version 5.0.0-rc.14 or later.
- Update ash_authentication_phoenix to version 2.17.4 or later.
- Update ash_authentication_phoenix to version 3.0.0-rc.0 or later.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-86533.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-86533 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-86533
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-86533 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-86533 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Sep. 17, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-86533', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'yes'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-09-17T18:13:50.422619Z'} -
New CVE Received by 6b3ad84c-e1a6-4bf7-a703-f496b71e49db
Sep. 17, 2026
Action Type Old Value New Value Added 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. Added CVSS V4.0 AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CWE CWE-613 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/86xxx/CVE-2026-86533.json">CVE-2026-86533</a> Added Reference https://cna.erlef.org/cves/CVE-2026-86533.html Added Reference https://github.com/team-alembic/ash_authentication/commit/a3f49f758f013d2ff086dd9c5ef2d94e921711b4 Added Reference https://github.com/team-alembic/ash_authentication/commit/e28e911caa9728d76329afdb0fb26742ffe4eeef Added Reference https://github.com/team-alembic/ash_authentication/commit/fcaeb73f76f8f2e9aef8bf637690d2a20dd97596 Added Reference https://github.com/team-alembic/ash_authentication/security/advisories/GHSA-w374-hvrx-66hg Added Reference https://github.com/team-alembic/ash_authentication_phoenix/commit/0135217e34e621dac79ae3d9559aeee49304b0aa Added Reference https://github.com/team-alembic/ash_authentication_phoenix/commit/a3253fb4fc7145aeb403537af1c24d3a8d51ffb1 Added Reference https://github.com/team-alembic/ash_authentication_phoenix/commit/f7ab005a2aac09707a25521653c94893d328cc52 Added Reference https://github.com/team-alembic/ash_authentication_phoenix/security/advisories/GHSA-m6x4-4gvp-xwjr Added Reference https://osv.dev/vulnerability/EEF-CVE-2026-86533