Advisory record · GHSA-x8mh-94wc-33gv

apache-airflow-providers-smtp: No certificate validation on SMTP STARTTLS connections in SMTP provider

CVSS 5.9 MediumEPSS 0.0027 · 19th percentile

Published by the GitHub Advisory Database at 30 Apr 2026, 12:33 UTC. agentprime has not analysed this yet, so whether it affects any app is not known.

PackageEcosystemAffectedFixed in
apache-airflow-providers-smtpPyPI>=2.0.0, <3.0.03.0.0
Identifiers
GHSA-x8mh-94wc-33gv · CVE-2026-41016 · PYSEC-2026-24
Weakness (CWE)
CWE-295
Published
30 Apr 2026
Updated
10 Sept 2026

Machine-written summary

Summary written by Claude Haiku from the source advisory. Not reviewed by a person.

Apache Airflow's apache-airflow-providers-smtp package, versions 2.0.0 up to but not including 3.0.0, does not validate certificates when it upgrades SMTP connections to TLS via STARTTLS. An attacker who can sit between the Airflow worker and the SMTP server (a man-in-the-middle) can present a self-signed certificate and capture the SMTP login credentials. Upgrade to apache-airflow-providers-smtp 3.0.0 or later, which contains the fix.

Written 1 Nov 2026.

Not analysed yet

We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.

Severity and exploitation

ScoreRatingCVSSVectorSource
5.9 Medium 3.1 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N GitHub Advisory Database
  • CISA KEV Not listed.
  • EPSS 0.0027, the 19th percentile, on 12 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

Timeline

  1. 31 Oct 2026, 14:11 UTC First seen by agentprime
  2. 31 Oct 2026, 14:11 UTC Confirmed by OSV

Sources

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.