Advisory record · PYSEC-2026-3990

Apache Airflow: the Core API logout endpoint revokes only a session token presented as the _token cookie. When a client logs out presenting its credential as an Authorization bearer header instead,...

CVSS 9.1 CriticalCriticalEPSS 0.0075 · 55th percentile

Critical, because:

  • CVSS score 9.1: 9.0 or more.

How we decide what’s critical

Published by OSV at 21 Sept 2026, 15:17 UTC. agentprime has not analysed this yet, so whether it affects any app is not known.

PackageEcosystemAffectedFixed in
apache-airflowPyPI>=3.0.0, <3.3.23.3.2
Identifiers
PYSEC-2026-3990 · BIT-airflow-2026-86473 · CVE-2026-86473
Weakness (CWE)
CWE-613
Published
21 Sept 2026
Updated
26 Sept 2026

Machine-written summary

Summary written by Claude Haiku from the source advisory. Not reviewed by a person.

Apache Airflow versions 3.0.0 before 3.3.2 are affected. When a client logs out with its token sent as an Authorization bearer header, the Core API logout endpoint returns a normal response but does not revoke the token, so it stays valid until it expires (24 hours by default). An attacker who already holds a copy of a valid token can keep access after the victim logs out, though they gain no privileges beyond the victim's own. Upgrade to apache-airflow 3.3.2 or later.

Written 1 Nov 2026.

Not analysed yet

We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.

Severity and exploitation

ScoreRatingCVSSVectorSource
9.1 Critical 3.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N OSV
  • CISA KEV Not listed.
  • EPSS 0.0075, the 55th percentile, on 12 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

Timeline

  1. 21 Sept 2026, 14:33 UTC Confirmed by the CVE List
  2. 21 Sept 2026, 15:17 UTC Confirmed by NVD
  3. 31 Oct 2026, 14:09 UTC First seen by agentprime
  4. 31 Oct 2026, 14:09 UTC Confirmed by OSV

Sources

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.