Apache Airflow exception-node deserialization permits arbitrary callable executionGHSA-8prw-8m6x-8w6f
HIGHFix: apache/airflow#68511GHSA-8prw-8m6x-8w6f is a high-severity (CVSS 8.8) Deserialization of Untrusted Data vulnerability in apache-airflow. A fix is available for apache-airflow — see the affected versions and patch details below.
Exploitation Status
No confirmed exploitation observed yet
- 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 GHSA-8prw-8m6x-8w6f.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
GHSA-8prw-8m6x-8w6f by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 394,803 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
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 serialization layer reconstructed exception nodes by calling import_string() on a class name taken from the serialized blob and instantiating it with arguments from the same blob, with no restriction on what could be imported. An operator's executor_config reaches that branch, so a Dag author could place a value there that causes an arbitrary callable to be imported and invoked -- for example subprocess.check_output, or builtins.eval on the builtins-prefixed variant. The code runs in the Scheduler, which reconstructs serialized Dags in its normal loop with no request involved, and in the API server, on any authenticated read of the Dag such as GET /api/v2/dags/{dag_id}/details. Both are components the Airflow security model states must never execute Dag-author code, and both hold the metadata database credentials and the JWT signing secret. No non-default configuration is required. This is a different sink from CVE-2026-33264, which covered only the trigger branch of the same deserializer: deployments that upgraded in response to that advisory are still affected through the exception branch and must upgrade again. Users are advised to upgrade to apache-airflow 3.3.1 or later, which restricts the imported class to a subclass of BaseException.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | apache-airflow | ≥ 3.3.0&&< 3.3.1 | 3.3.1pip install --upgrade 'apache-airflow==3.3.1' |
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 3.3.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-8prw-8m6x-8w6f is resolved across your whole dependency graph.
Workarounds
Do not deserialise data from untrusted sources: where the format allows it, restrict deserialisation to an explicit allowlist of expected types, and prefer a data-only format (JSON, Protobuf) over one that can reconstruct arbitrary objects until you can upgrade.
Frequently Asked Questions
Is GHSA-8prw-8m6x-8w6f in your dependencies?
Find it across PyPI, including transitive dependencies.