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TI-2026-26224 Aliases CVE-2026-33858GHSA-mc4f-r875-v87w

Apache Airflow: Unsafe Deserialization via Legacy Serialization Keys (__type/__var) Bypass in XCom API

Priority MEDIUM 41CWE-502Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA and GitHub. Impact type from CWE-502.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00592 48th percentileScored 2026-11-07
Fix Fixed Apache Airflow (Apache Software Foundation): 3.2.0apache-airflow (PyPI): 3.2.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
ApacheApache Airflow3.1.8 to before 3.2.03.2.0Patch availableCNA
—apache-airflow (PyPI)3.1.8 to before 3.2.03.2.0Patch availableGHSA-mc4f-r875-v87w
  • Apache Airflow VendorApache Affected 3.1.8 to before 3.2.0 Fixed in 3.2.0 Patch available CNA
  • apache-airflow (PyPI) Vendor— Affected 3.1.8 to before 3.2.0 Fixed in 3.2.0 Patch available GHSA-mc4f-r875-v87w

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:apache:airflow:*:*:*:*:*:*:*:*3.1.8 to before 3.2.0VulnerableApache
  • cpe:2.3:a:apache:airflow:*:*:*:*:*:*:*:* Versions 3.1.8 to before 3.2.0 Vulnerable ·Apache

Remediation

  • Fix · CNA Apache Airflow (Apache Software Foundation) Fixed in 3.2.0
  • Fix · GHSA-mc4f-r875-v87w apache-airflow (PyPI) Fixed in 3.2.0 Advisory →

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    Apache Airflow 3.2.0

    2 records Highest priority Priority MEDIUM 1 MEDIUM, 1 LOW

    Other records, highest priority first

    • TI-2025-40728 Apache Airflow: Secrets from Airflow config file logged in plain text in DAG run logs UIPriority LOW 39
    Show all 2 records →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-33858
  2. 2026-10-03 Alias added: GHSA-mc4f-r875-v87w
  3. 2026-10-25 EPSS moved to the below the 50th percentile
  4. 2026-11-03 Fix available: [email protected] · CNA

References

Patch 1

Advisory 3

Other 2

  • TI-2020-10905 Missing authentication in Apache Airflow KEVCVSS 3.1CRITICAL 9.8
  • TI-2020-09638 OS command injection in Apache Airflow KEVCVSS 3.1HIGH 8.8
  • TI-2022-19017 Apache Airflow <2.4.0 has an RCE in a bash example CVSS 3.1HIGH 8.8
  • TI-2021-16140 Apache Airflow: Variable Import endpoint missed authentication check CVSS 3.1CRITICAL 9.8
  • TI-2022-08169 Apache Airflow: RCE in example DAGs CVSS 3.1HIGH 8.8
  • TI-2024-26776 Apache Airflow: DAG Author Code Execution possibility in airflow-scheduler CVSS 3.1HIGH 8.8
See all 157 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences