What is CVE-2026-33858?

CVE-2026-33858 is a high-severity vulnerability in Apache Airflow, classified under Deserialization of Untrusted Data. CVSS score: 8.8/10. Published 2026-04-13.

How severe is CVE-2026-33858?

High severity. CVSS v3 base score is 8.8 out of 10.

Deserialization in Apache Airflow

CVE-2026-33858

Dag Authors, who normally should not be able to execute code in the webserver context could craft XCom payload causing the webserver to execute arbitrary code. Since Dag Authors are already highly trusted, severity of this issue is Low. Users are recommended to upgrade to Apache Airflow 3.2.0, which resolves this issue.

Vulnerability class: Insecure Deserialization

Published 2026-04-13 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.011 (63.9th percentile), scored 2026-10-19.

Low probability of exploitation in the next 30 days, but still tracked. 64th percentile — 63.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.006 · newest: 0.011 · change: +0.005

Affected products

Apache Airflow
Apache Software Foundation Airflow — versions 3.1.8

Weakness classification (CWE)

CWE-502 — Deserialization of Untrusted Data

References

github.com/apache/airflow/pull/64148 (patch, Issue Tracking)
lists.apache.org/thread/1npt3o2x81s0gw9tmfcv4n7p1z9hdmy0 (vendor-advisory, Mailing List, Vendor Advisory)
af854a3a-2127-422b-91ae-364da2661108 (Mailing List, Third Party Advisory)

Frequently asked questions

What is CVE-2026-33858?: CVE-2026-33858 is a high-severity vulnerability in Apache Airflow, classified under Deserialization of Untrusted Data. CVSS score: 8.8/10. Published 2026-04-13.
How severe is CVE-2026-33858?: High severity. CVSS v3 base score is 8.8 out of 10.