How severe is CVE-2026-41016?

CVE-2026-41016 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2026-41016 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (18th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-41016?

CVE-2026-41016 affects Apache Airflow. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-41016?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-41016 have an EU (EUVD) identifier?

Yes. CVE-2026-41016 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-26359.

When was CVE-2026-41016 published?

CVE-2026-41016 was published on 2026-04-30 and last updated on 2026-06-17.

CVE-2026-41016

CVE-2026-41016 is a medium-severity vulnerability in Apache Airflow with a CVSS 3.x base score of 5.9. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-295.

Key facts

Severity: Medium (CVSS 3.x base score 5.9)
EPSS exploit prediction: 0% (18th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-26359
Weakness: CWE-295
Affected product: Apache Airflow
Published: 2026-04-30
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2026-41016?: 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 severe is CVE-2026-41016?: CVE-2026-41016 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2026-41016 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (18th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-41016?: CVE-2026-41016 affects Apache Airflow. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-41016?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-41016 have an EU (EUVD) identifier?: Yes. CVE-2026-41016 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-26359.
When was CVE-2026-41016 published?: CVE-2026-41016 was published on 2026-04-30 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:apache:airflow:*:*:*:*:*:*:*:*

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