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TI-2026-29667 Aliases CVE-2026-41016GHSA-x8mh-94wc-33gv

Apache Airflow Providers SMTP: No certificate validation on SMTP STARTTLS connections in SMTP provider

Priority LOW 26CWE-295Published · Updated

Key facts

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

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA and GitHub. Impact type from CWE-295.

Summary

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 could present a self-signed certificate, complete the STARTTLS upgrade, and capture the SMTP credentials sent during the subsequent `login()` call. Users are advised to upgrade to the `apache-airflow-providers-smtp` version that contains the fix.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00268 19th percentileScored 2026-11-07
Fix Fixed Apache Airflow Providers SMTP (Apache Software Foundation): 3.0.0apache-airflow-providers-smtp (PyPI): 3.0.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

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 Airflow Providers SMTP2.0.0 to before 3.0.03.0.0Patch availableCNA
—apache-airflow-providers-smtp (PyPI)2.0.0 to before 3.0.03.0.0Patch availableGHSA-x8mh-94wc-33gv
  • Apache Airflow Providers SMTP VendorApache Affected 2.0.0 to before 3.0.0 Fixed in 3.0.0 Patch available CNA
  • apache-airflow-providers-smtp (PyPI) Vendor— Affected 2.0.0 to before 3.0.0 Fixed in 3.0.0 Patch available GHSA-x8mh-94wc-33gv

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:apache:airflow:*:*:*:*:*:*:*:*2.0.0 to before 3.0.0VulnerableApache
  • cpe:2.3:a:apache:airflow:*:*:*:*:*:*:*:* Versions 2.0.0 to before 3.0.0 Vulnerable ·Apache

Remediation

  • Fix · CNA Apache Airflow Providers SMTP (Apache Software Foundation) Fixed in 3.0.0
  • Fix · GHSA-x8mh-94wc-33gv apache-airflow-providers-smtp (PyPI) Fixed in 3.0.0 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-41016
  2. 2026-10-03 Alias added: GHSA-x8mh-94wc-33gv

References

Patch 1

Advisory 2

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