CVE-2026-41016
apache-airflow-providers-smtp: No certificate validation on SMTP STARTTLS connections in SMTP provider
Description
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.
How to fix CVE-2026-41016
To remediate CVE-2026-41016, upgrade the affected package to a fixed version below.
- —upgrade to 3.0.0 or later
- —upgrade to 3.0.0 or later
Is CVE-2026-41016 being exploited?
Low — EPSS is 0.0%, meaning exploitation activity has not been observed at scale.
Affected packages (2)
- >= 2.0.0, < 3.0.0
- >= 2.0.0, < 3.0.0
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | MEDIUM5.9 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N |