What is CVE-2026-41016?

CVE-2026-41016 is a medium-severity vulnerability in Apache Airflow, classified under Improper Certificate Validation. CVSS score: 5.9/10. Published 2026-04-30.

How severe is CVE-2026-41016?

Medium severity. CVSS v3 base score is 5.9 out of 10.

Vulnerability in Apache Airflow

CVE-2026-41016

Apache Airflow's SMTP provider `SmtpHook` called Python's `smtplib.SMTP.starttls()` without an SSL context, so no certificate validation was performed on the TLS upgrade. A man-in-the-middle between the Airflow worker and the SMTP server c…

Vulnerability class: Improper Certificate Validation

EPSS: 0.000 (6.5th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.9 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N.

Affected products

Apache Airflow
Apache Software Foundation Airflow Providers Smtp — versions 2.0.0

Weakness classification (CWE)

CWE-295 — Improper Certificate Validation

References

security@apache.org (Patch, patch, Issue Tracking)
security@apache.org (vendor-advisory, Mailing List, Vendor Advisory)

Frequently asked questions

What is CVE-2026-41016?: CVE-2026-41016 is a medium-severity vulnerability in Apache Airflow, classified under Improper Certificate Validation. CVSS score: 5.9/10. Published 2026-04-30.
How severe is CVE-2026-41016?: Medium severity. CVSS v3 base score is 5.9 out of 10.