Vulnerability-Lookup

PYSEC-2026-24

Vulnerability from pysec - Published: 2026-04-30 10:16 - Updated: 2026-05-20 09:18

Details

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.

Severity

5.9 (Medium)


                  
                    CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

Impacted products

Name	purl
apache-airflow-providers-smtp	pkg:pypi/apache-airflow-providers-smtp

Aliases

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "apache-airflow-providers-smtp",
        "purl": "pkg:pypi/apache-airflow-providers-smtp"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "2.0.0"
            },
            {
              "fixed": "3.0.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2.0.0",
        "2.0.1",
        "2.0.1rc1",
        "2.0.2",
        "2.0.2rc1",
        "2.0.3",
        "2.0.3rc1",
        "2.1.0",
        "2.1.0rc1",
        "2.1.1",
        "2.1.1rc1",
        "2.1.2",
        "2.1.2rc1",
        "2.2.0",
        "2.2.0rc1",
        "2.2.1",
        "2.2.1rc1",
        "2.3.0",
        "2.3.0rc1",
        "2.3.1",
        "2.3.1rc1",
        "2.3.2",
        "2.3.2rc1",
        "2.4.0",
        "2.4.0rc1",
        "2.4.1",
        "2.4.1rc1",
        "2.4.2",
        "2.4.2rc1",
        "2.4.3",
        "2.4.3rc1",
        "2.4.4",
        "2.4.4rc1",
        "2.4.5",
        "2.4.5rc1",
        "3.0.0rc1"
      ]
    }
  ],
  "aliases": [
    "CVE-2026-41016",
    "GHSA-x8mh-94wc-33gv"
  ],
  "details": "Apache Airflow\u0027s SMTP provider `SmtpHook` called Python\u0027s `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.",
  "id": "PYSEC-2026-24",
  "modified": "2026-05-20T09:18:52.135285Z",
  "published": "2026-04-30T10:16:01.930Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://lists.apache.org/thread/gb202qy5r31bgdd3d51d7s5o1jh40kc4"
    },
    {
      "type": "FIX",
      "url": "https://github.com/apache/airflow/pull/65346"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/advisories/GHSA-x8mh-94wc-33gv"
    }
  ],
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-41016 (GCVE-0-2026-41016)

Vulnerability from cvelistv5 – Published: 2026-04-30 09:09 – Updated: 2026-04-30 13:17

Title

Apache Airflow Providers SMTP: No certificate validation on SMTP STARTTLS connections in SMTP provider

Summary

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.

Severity

5.9 (Medium)


                        
                          CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-04-30 13:16 UTC

CWE

CWE-295 - Improper Certificate Validation

Assigner

apache mitre root Scorecard

References

2 references

URL	Tags
https://github.com/apache/airflow/pull/65346	patch
https://lists.apache.org/thread/gb202qy5r31bgdd3d…	vendor-advisory

Impacted products

1 product

Vendor	Product	Version
Apache Software Foundation	Apache Airflow Providers SMTP	Affected: 2.0.0 , < 3.0.0 (semver)

Credits

Francis Bergin (@francisbergin) Jarek Potiuk

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "cvssV3_1": {
              "attackComplexity": "HIGH",
              "attackVector": "NETWORK",
              "availabilityImpact": "NONE",
              "baseScore": 5.9,
              "baseSeverity": "MEDIUM",
              "confidentialityImpact": "HIGH",
              "integrityImpact": "NONE",
              "privilegesRequired": "NONE",
              "scope": "UNCHANGED",
              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N",
              "version": "3.1"
            }
          },
          {
            "other": {
              "content": {
                "id": "CVE-2026-41016",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-04-30T13:16:50.020130Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-04-30T13:17:14.490Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "collectionURL": "https://pypi.python.org",
          "defaultStatus": "unaffected",
          "packageName": "apache-airflow-providers-smtp",
          "product": "Apache Airflow Providers SMTP",
          "vendor": "Apache Software Foundation",
          "versions": [
            {
              "lessThan": "3.0.0",
              "status": "affected",
              "version": "2.0.0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "Francis Bergin (@francisbergin)"
        },
        {
          "lang": "en",
          "type": "remediation developer",
          "value": "Jarek Potiuk"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "Apache Airflow\u0027s SMTP provider `SmtpHook` called Python\u0027s `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."
            }
          ],
          "value": "Apache Airflow\u0027s SMTP provider `SmtpHook` called Python\u0027s `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."
        }
      ],
      "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": {
        "dateUpdated": "2026-04-30T09:09:45.529Z",
        "orgId": "f0158376-9dc2-43b6-827c-5f631a4d8d09",
        "shortName": "apache"
      },
      "references": [
        {
          "tags": [
            "patch"
          ],
          "url": "https://github.com/apache/airflow/pull/65346"
        },
        {
          "tags": [
            "vendor-advisory"
          ],
          "url": "https://lists.apache.org/thread/gb202qy5r31bgdd3d51d7s5o1jh40kc4"
        }
      ],
      "source": {
        "discovery": "UNKNOWN"
      },
      "title": "Apache Airflow Providers SMTP: No certificate validation on SMTP STARTTLS connections in SMTP provider",
      "x_generator": {
        "engine": "airflow-s/generate_cve_json.py"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "f0158376-9dc2-43b6-827c-5f631a4d8d09",
    "assignerShortName": "apache",
    "cveId": "CVE-2026-41016",
    "datePublished": "2026-04-30T09:09:45.529Z",
    "dateReserved": "2026-04-16T02:38:58.158Z",
    "dateUpdated": "2026-04-30T13:17:14.490Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

GHSA-X8MH-94WC-33GV

Vulnerability from github – Published: 2026-04-30 12:33 – Updated: 2026-05-22 13:04

Summary

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

Details

Severity

5.9 (Medium)


                  
                    CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

Show details on source website

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "apache-airflow-providers-smtp"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "2.0.0"
            },
            {
              "fixed": "3.0.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-41016"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-295"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-05-22T13:04:58Z",
    "nvd_published_at": "2026-04-30T10:16:01Z",
    "severity": "MODERATE"
  },
  "details": "Apache Airflow\u0027s SMTP provider `SmtpHook` called Python\u0027s `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.",
  "id": "GHSA-x8mh-94wc-33gv",
  "modified": "2026-05-22T13:04:58Z",
  "published": "2026-04-30T12:33:11Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-41016"
    },
    {
      "type": "WEB",
      "url": "https://github.com/apache/airflow/pull/65346"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/apache/airflow"
    },
    {
      "type": "WEB",
      "url": "https://github.com/pypa/advisory-database/tree/main/vulns/apache-airflow-providers-smtp/PYSEC-2026-24.yaml"
    },
    {
      "type": "WEB",
      "url": "https://lists.apache.org/thread/gb202qy5r31bgdd3d51d7s5o1jh40kc4"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "apache-airflow-providers-smtp: No certificate validation on SMTP STARTTLS connections in SMTP provider"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

Action not permitted

PYSEC-2026-24

CVE-2026-41016 (GCVE-0-2026-41016)

GHSA-X8MH-94WC-33GV

Tags

Sightings

Nomenclature

Related by attack behaviour