CVE Catalog

CVE-2026-41016

MediumCVSS 5.9
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.27%

19th percentile - higher than 19% of all known CVEs

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.

Risk Assessment

Interception of SMTP credentials could allow an attacker to send messages on behalf of the organization or gain further access to the mail server. The risk applies to environments where the Airflow worker connects to the SMTP server over an untrusted network.

Recommendation

Upgrade the apache-airflow-providers-smtp package to a version containing the fix. Consider rotating the SMTP credentials used by Airflow.

Related vulnerabilities

Original NVD description (English source)

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.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS