{"id":"CVE-2026-41016","state":"PUBLISHED","title":"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.","publishedAt":"2026-04-30T09:09:45.529Z","updatedAt":"2026-04-30T13:17:14.490Z","severity":{"score":5.9,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N","source":"CISA-ADP"},"assigner":"apache","products":["Apache Software Foundation Apache Airflow Providers SMTP"],"affected":[{"vendor":"Apache Software Foundation","product":"Apache Airflow Providers SMTP","packageName":"apache-airflow-providers-smtp","defaultStatus":"unaffected","versions":[{"version":"2.0.0","status":"affected","lessThan":"3.0.0","versionType":"semver"}],"collectionURL":"https://pypi.python.org"}],"references":["https://github.com/apache/airflow/pull/65346","https://lists.apache.org/thread/gb202qy5r31bgdd3d51d7s5o1jh40kc4"],"weaknesses":["CWE-295"],"ingestedAt":"2026-10-29T20:11:57.932Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/41xxx/CVE-2026-41016.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-41016","state":"PUBLISHED","datePublished":"2026-04-30T09:09:45.529Z","dateUpdated":"2026-04-30T13:17:14.490Z","assignerShortName":"apache","assignerOrgId":"f0158376-9dc2-43b6-827c-5f631a4d8d09","dateReserved":"2026-04-16T02:38:58.158Z"},"containers":{"cna":{"title":"Apache Airflow Providers SMTP: No certificate validation on SMTP STARTTLS connections in SMTP provider","descriptions":[{"lang":"en","value":"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."}],"affected":[{"vendor":"Apache Software Foundation","product":"Apache Airflow Providers SMTP","packageName":"apache-airflow-providers-smtp","defaultStatus":"unaffected","versions":[{"version":"2.0.0","status":"affected","lessThan":"3.0.0","versionType":"semver"}],"collectionURL":"https://pypi.python.org"}],"references":[{"url":"https://github.com/apache/airflow/pull/65346","tags":["patch"]},{"url":"https://lists.apache.org/thread/gb202qy5r31bgdd3d51d7s5o1jh40kc4","tags":["vendor-advisory"]}],"metrics":[{"other":{"content":{"text":"low"},"type":"Textual description of severity"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-295","description":"CWE-295: Improper Certificate Validation","lang":"en","type":"CWE"}]}],"providerMetadata":{"shortName":"apache","orgId":"f0158376-9dc2-43b6-827c-5f631a4d8d09","dateUpdated":"2026-04-30T09:09:45.529Z"},"credits":[{"lang":"en","type":"finder","value":"Francis Bergin (@francisbergin)"},{"lang":"en","type":"remediation developer","value":"Jarek Potiuk"}],"source":{"discovery":"UNKNOWN"},"x_generator":{"engine":"airflow-s/generate_cve_json.py"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"cvssV3_1":{"scope":"UNCHANGED","version":"3.1","baseScore":5.9,"attackVector":"NETWORK","baseSeverity":"MEDIUM","vectorString":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N","integrityImpact":"NONE","userInteraction":"NONE","attackComplexity":"HIGH","availabilityImpact":"NONE","privilegesRequired":"NONE","confidentialityImpact":"HIGH"}},{"other":{"type":"ssvc","content":{"timestamp":"2026-04-30T13:16:50.020130Z","id":"CVE-2026-41016","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-04-30T13:17:14.490Z"}}]}}}