CVE-2026-33264Apache Airflow: DAG author RCE on webserver via unrestricted import_string() in BaseSerialization.deserialize()
- 9.8CriticalCVSS base score
- 1.6%Exploitation in 30 daysEPSS · top 23% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
A bug in `BaseSerialization.deserialize()` allowed unrestricted `import_string()` of attacker-controlled class paths when the Scheduler / API Server loaded a serialized DAG: a DAG author could embed a malicious trigger into a DAG to gain remote code execution on the API Server / Scheduler process, crossing the Airflow security boundary that DAG-author code must never execute in those processes. Users are advised to upgrade to `apache-airflow` 3.3.0 or later. As a defense-in-depth mitigation, deployments where DAG-author trust is limited can restrict the `[core] allowed_deserialization_classes` config to a narrow allowlist.
Timeline
ID reserved
By apache
- 4 months later
· 4 months later
Published
- 4 months later
· 4 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| CISA-ADPADP (enrichment) | 3.1 | Critical9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVDNVD · Analyzed | 3.1 | Critical9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 1.6% · top 23% of all CVEs (13 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: yes · Technical impact: total
The list uses the assigner's score when there is one, then CISA's, then NVD's: Critical 9.8.
Affected products
Apache Software Foundation · Apache Airflow
- affected < 3.0.0
Apache Software Foundation · Apache Airflow
- affected 3.0.0 – < 3.3.0
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- PyPIapache-airflowGHSA-2943-9672-r45w (opens in a new tab)
References
References4
- https://github.com/apache/airflow/pull/66002 (opens in a new tab)patch
- https://github.com/apache/airflow/pull/68528 (opens in a new tab)patch
- https://lists.apache.org/thread/otvdw8qt2y7xy2n5nq9xby9ky4rf5ltj (opens in a new tab)vendor-advisory
- http://www.openwall.com/lists/oss-security/2026/07/07/1 (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-42030 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-2943-9672-r45w (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-33264)Record last updated .