Home/CVE/Apache Airflow's SMTP provider `SmtpHook` called Python's `smtplib.SMTP.starttls()` without an SSL context, so no certif
CVE

CVE-2026-41016

Apache Airflow's SMTP provider `SmtpHook` called Python's `smtplib.SMTP.starttls()` without an SSL context, so no certif

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.

MEDIUM · CVSS 5.9 EPSS 0.00022
Monitor
  • No active-exploitation, high-EPSS, or public-exploit signals - routine patching cadence
Sigma rules0 YARA rules0
⬡

Weakness Classification

CWE-295Improper Certificate Validation
▤

Affected Products & Versions

1
apache airflow>= 2.0.0 and < 3.0.0
▣

Scoring & Timeline

5.9
MEDIUM · CVSS v3.1 · security@apache.org
View on NVD
Attack Vector
Network Adjacent Local Physical
Attack Complexity
Low High
Privileges Required
None Low High
User Interaction
None Required
Scope
Unchanged Changed
Confidentiality
None Low High
Integrity
None Low High
Availability
None Low High
Published to NVD30 Apr 2026 · 10:16 AM
CVSS VectorCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
SSVC triage · cisa-vulnrichment
Exploitation
none
Automatable
no
Technical impact
partial
SSVC asks the questions that actually drive patch urgency: is it being exploited, can attacks be automated, and how total is the impact.
🔗

References & Sources

2
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
https://github.com/apache/airflow/pull/65346Issue TrackingPatch
https://lists.apache.org/thread/gb202qy5r31bgdd3d51d7s5o1jh40kc4Mailing ListVendor Advisory
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