# CVE-2026-25917: Apache Airflow: API extra-links triggers XCom deserialization/class instantiation (Airflow 3.1.5)

Status: published. Published: 2026-04-18. Updated: 2026-11-03.

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 fixes the issue.

## Remediation

- fix: The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches. (source: CNA: apache) — https://github.com/apache/airflow/pull/61641

## Affected products and versions

- Apache Software Foundation / Apache Airflow (apache-airflow): ≥ 0; < 3.0.0 (affected, semver). Source: CNA: apache
- Apache Software Foundation / Apache Airflow (apache-airflow-core): ≥ 3.0.0; < 3.2.0 (affected, semver). Source: CNA: apache

## Severity and prioritization

- CVSS 3.1: 7.2 (high); CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H; source: ADP: CISA-ADP

- CISA KEV: No listing in collected sources

- EPSS: 0.82% as of 2026-11-02; percentile 57.32%

- SSVC: exploitation none; automatable no; technical impact total; source ADP: CISA-ADP

- Weaknesses: CWE-502

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://github.com/apache/airflow/pull/61641 (CNA: apache; patch)

- https://lists.apache.org/thread/6whgpkqbh12rvpfmvcg8b0vwlv4hq3po (CNA: apache; vendor-advisory)

- http://www.openwall.com/lists/oss-security/2026/04/17/9 (ADP: CVE)

## Provenance

- CNA: apache: https://www.cve.org/CVERecord?id=CVE-2026-25917; retrieved 2026-11-03; source updated 2026-11-03

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2026-25917; retrieved 2026-11-03; source updated Not reported

Revision: 1ddd6b220191cb007cd5315fa673ad95e7ffb9b3e73e23199786aa65abb1c3f3

Canonical: https://y2.dev/cve/CVE-2026-25917

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