CVE-2026-45426

CVE-2026-45426: Apache Airflow: Log server JWT authorization bypass via Python lstrip() character stripping allows cross-Dag log access

Vendor Apache Software Foundation
Product Apache Airflow
Weakness CWE-863 · Incorrect authorization
Published June 1, 2026
Last update June 1, 2026

CVSS base score

What the vulnerability does

Description

Exploitation requires the attacker to already be an authenticated Airflow worker holding a valid Log-server JWT issued for at least one Dag. Apache Airflow's Log server authorized JWT tokens against Dag IDs by applying Python's `str.lstrip()` to the requested path segment when verifying the JWT's `sub` claim. `str.lstrip()` strips any of a *set* of characters from the left (not a prefix), so a JWT issued for a Dag named e.g. `dag_a` would authorize log access to any other Dag whose name began with any subset of the characters `{d, a, g, _}` (e.g. `dag_attacker`, `aaaa_target`, `_dag_secret`). Such an authenticated worker could enumerate and read worker logs of other Dags whose names happened to share that character-class prefix, leaking task output and error traces beyond the documented per-Dag isolation boundary. Affects deployments relying on per-Dag log-access scoping (multi-team, shared-executor, shared-worker topologies). Users are advised to upgrade to `apache-airflow` 3.2.2 or later.

Key dates

Disclosure timeline

June 1, 2026 CVE published
June 1, 2026 Record updated