---
id: CVE-2026-49267
aliases:
  - GHSA-799x-qp47-8qwq
  - BIT-airflow-2026-49267
title: Apache Airflow has no certificate validation on SMTP STARTTLS connections
summary: Apache Airflow has no certificate validation on SMTP STARTTLS connections
severity: medium
cvss: 5.9
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N'
vendor: apache-airflow
product: apache-airflow
ecosystem: pip
affected:
  - 'apache-airflow >= 2.0.0, < 3.2.2'
patched:
  - apache-airflow 3.2.2
published: '2026-06-01'
updated: '2026-07-09'
source: OSV
sourceUrl: 'https://osv.dev/vulnerability/GHSA-799x-qp47-8qwq'
references:
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-49267'
  - url: 'https://github.com/apache/airflow/pull/65346'
  - url: 'https://github.com/apache/airflow'
  - url: 'https://lists.apache.org/thread/6v2ds757000msmjmovnnqryqzks83ps0'
tags:
  - osv
  - pip
epss: 0.00268
epssPercentile: 0.16863
ingestedAt: '2026-07-10T13:49:10.582Z'
---

## Overview

Apache Airflow's EmailOperator and the underlying `airflow.utils.email` helpers established SMTP STARTTLS connections without verifying the remote certificate when the deployment used `[email] smtp_starttls=True` without `[email] smtp_ssl`. An attacker positioned between the worker and the configured SMTP server (network MITM — typical hostile-network attack-surface for environments where the SMTP relay sits outside the worker's trust boundary) could present a self-signed certificate, have the worker complete the STARTTLS handshake silently, and capture the SMTP AUTH credentials and message contents the worker forwarded.

This CVE covers the **core apache-airflow side** of the same root cause already covered for the SMTP provider by `CVE-2026-41016` (published 2026-04-27, covering `apache-airflow-providers-smtp`). Users who already applied the SMTP-provider fix from CVE-2026-41016 should additionally upgrade `apache-airflow` to 3.2.2 or later to cover the core-side path through `airflow.utils.email`. Affects deployments configured with `smtp_starttls=True` and `smtp_ssl=False` where the SMTP relay is reachable across a less-trusted network segment than the worker.

Users are advised to upgrade to `apache-airflow` 3.2.2 or later.

## Affected packages

- `apache-airflow >= 2.0.0, < 3.2.2`

## Remediation

Upgrade to a patched release:

- `apache-airflow 3.2.2`