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 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.

CVSS v3 5.9 MEDIUM

5.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/apache/airflow/pull/65346	Issue Tracking Patch
https://lists.apache.org/thread/gb202qy5r31bgdd3d51d7s5o1jh40kc4	Mailing List Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:apache:airflow:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-04-30 10:16

Updated : 2026-06-17 10:46

NVD link : CVE-2026-41016

Mitre link : CVE-2026-41016

CVE.ORG link : CVE-2026-41016

JSON object : View

Products Affected

apache

airflow

CWE

CWE-295

Improper Certificate Validation

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