CVE-2026-86533

CRITICALPre-NVD 9.19.1—
EchelonGraph scoreMEDIUM confidence

This critical-severity CVE scores 9.1 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.6%, top 50% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, secondary
Trending — 3 sources updated this week
9.1EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 1%CVSS: 9.1Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

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.

CVSS v3
9.1
EG Score
9.1(medium)
EG Risk
56(Track)
EG Risk 56/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity91% × 45%
Exploitation1% × 40%
Automatability100% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
1%
EPSS %ILE
50%
KEV
Not listed

Published

September 17, 2026

Last Modified

September 18, 2026

Advisory Details (10)

Auto-updated Sep 17, 2026
Patch available. Sources: github_commit, github.
github_commit Patch Available

commit e28e911caa97 (team-alembic/ash_authentication)

Patch available: team-alembic/ash_authentication v5.0.0-rc.14 (contains commit e28e911caa97)

https://github.com/team-alembic/ash_authentication/commit/e28e911caa9728d76329afdb0fb26742ffe4eeef
github_commit Patch Available

commit a3f49f758f01 (team-alembic/ash_authentication)

Patch available: team-alembic/ash_authentication v4.15.0 (contains commit a3f49f758f01)

https://github.com/team-alembic/ash_authentication/commit/a3f49f758f013d2ff086dd9c5ef2d94e921711b4
github_commit Patch Available

commit fcaeb73f76f8 (team-alembic/ash_authentication)

Patch available: team-alembic/ash_authentication v4.9.7 (contains commit fcaeb73f76f8)

https://github.com/team-alembic/ash_authentication/commit/fcaeb73f76f8f2e9aef8bf637690d2a20dd97596
github_commit Patch Available

commit f7ab005a2aac (team-alembic/ash_authentication_phoenix)

Patch available: team-alembic/ash_authentication_phoenix v2.17.4 (contains commit f7ab005a2aac)

https://github.com/team-alembic/ash_authentication_phoenix/commit/f7ab005a2aac09707a25521653c94893d328cc52
github_commit Patch Available

commit 0135217e34e6 (team-alembic/ash_authentication_phoenix)

Patch available: team-alembic/ash_authentication_phoenix v3.0.0-rc.11 (contains commit 0135217e34e6)

https://github.com/team-alembic/ash_authentication_phoenix/commit/0135217e34e621dac79ae3d9559aeee49304b0aa
github_commit Patch Available

commit a3253fb4fc71 (team-alembic/ash_authentication_phoenix)

Patch available: team-alembic/ash_authentication_phoenix v2.10.2 (contains commit a3253fb4fc71)

https://github.com/team-alembic/ash_authentication_phoenix/commit/a3253fb4fc7145aeb403537af1c24d3a8d51ffb1
github Patch Available

Session revocation has no effect under `session_identifier :jti`: the read path never checks it · Advisory · team-alembic/ash_authentication · GitHub

https://github.com/team-alembic/ash_authentication/security/advisories/GHSA-w374-hvrx-66hg
generic

OSV - Open Source Vulnerabilities

https://osv.dev/vulnerability/EEF-CVE-2026-86533
generic

CVE-2026-86533

https://cna.erlef.org/cves/CVE-2026-86533.html
github Patch Available

Revoked sessions stay authenticated in LiveViews under `session_identifier :jti` · Advisory · team-alembic/ash_authentication_phoenix · GitHub

https://github.com/team-alembic/ash_authentication_phoenix/security/advisories/GHSA-m6x4-4gvp-xwjr

Affected Packages

(2 across 1 ecosystem)
Hex(2)
PackageVulnerable rangeFixed inDependents
ash_authentication4.10.0 ... 5.0.0-rc.9 (37 versions)5.0.0-rc.14—
ash_authentication_phoenix2.10.0 ... 3.0.0-rc.9 (30 versions)3.0.0-rc.11—

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 7× in last 7d / 7× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-09-19 17:35 UTCEG score recompute
  2. 2026-09-18 22:21 UTCEG score recompute
  3. 2026-09-18 19:28 UTCEPSS rescore
  4. 2026-09-17 19:26 UTCEG score recompute
  5. 2026-09-17 18:18 UTCEG score recompute
  6. 2026-09-17 13:20 UTCEG score recompute
  7. 2026-09-17 13:19 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-86533?
CVE-2026-86533 is a critical vulnerability published on September 17, 2026. Insufficient Session Expiration vulnerability in team-alembic AshAuthentication and AshAuthentication Phoenix allows a revoked session to remain fully authenticated. A resource configured with sessionidentifier :jti and requiretokenpresenceforauthentication? disabled stores its session value as…
When was CVE-2026-86533 disclosed?
CVE-2026-86533 was first published in the National Vulnerability Database on September 17, 2026, with the most recent update on September 18, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-86533 actively exploited?
CVE-2026-86533 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 1% probability of exploitation in the next 30 days, which ranks it in the top 50.4% of all scored CVEs.
What is the CVSS score of CVE-2026-86533?
CVE-2026-86533 has a CVSS v3 base score of 9.1 (NVD).
How do I remediate CVE-2026-86533?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-86533, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-86533

Explore →

Is Your Infrastructure Affected by CVE-2026-86533?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Start Free Scan →Browse All CVEs