Vulnerability-Lookup

(CVE-2026-59243)

Vulnerability from cleanstart – Published: 2026-10-30 11:06 – Updated: 2026-10-09 07:45 – Source website

Summary

FAB auth manager's Azure AD OAuth login defaulted `verify_signature=False` when decoding the ID token, so an attacker able to present a forged or unsigned (`alg:none`) ID token to the OAuth callbac...

Details

Security vulnerability affects the airflow-3 package. The FAB auth manager's Azure AD OAuth login defaulted verify_signature=False when decoding the ID token, so an attacker able to present a forged or unsigned (alg:none) ID token to the OAuth callback could bypass authentication and log in as an arbitrary user, including one holding the Admin r....

Severity

9.8 (Critical)


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

References

URL

Type

	https://github.com/cleanstart-dev/cleanstart-secu…	ADVISORY
	https://osv.dev/vulnerability/CVE-2026-59243	WEB
	https://nvd.nist.gov/vuln/detail/CVE-2026-59243	WEB

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "CleanStart",
        "name": "airflow-3",
        "purl": "pkg:apk/cleanstart/airflow-3"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.0.6-r2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "credits": [],
  "database_specific": {},
  "details": "Security vulnerability affects the airflow-3 package. The FAB auth manager\u0027s Azure AD OAuth login defaulted `verify_signature=False` when decoding the ID token, so an attacker able to present a forged or unsigned (`alg:none`) ID token to the OAuth callback could bypass authentication and log in as an arbitrary user, including one holding the Admin r....",
  "id": "CLEANSTART-2026-KO00783",
  "modified": "2026-10-09T07:45:14Z",
  "published": "2026-10-30T11:06:44.944651Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/cleanstart-dev/cleanstart-security-advisories/tree/main/advisories/2026/CLEANSTART-2026-KO00783.json"
    },
    {
      "type": "WEB",
      "url": "https://osv.dev/vulnerability/CVE-2026-59243"
    },
    {
      "type": "WEB",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-59243"
    }
  ],
  "related": [],
  "schema_version": "1.7.3",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "FAB auth manager\u0027s Azure AD OAuth login defaulted `verify_signature=False` when decoding the ID token, so an attacker able to present a forged or unsigned (`alg:none`) ID token to the OAuth callbac...",
  "upstream": [
    "CVE-2026-59243"
  ]
}

CVE-2026-59243 (GCVE-0-2026-59243)

Vulnerability from cvelistv5 – Published: 2026-07-29 08:35 – Updated: 2026-09-16 14:56

Title

Apache Airflow FAB provider: FAB auth manager: JWT signature verification disabled by default for Azure AD OAuth (`verify_signature` defaults to `False`)

Summary

The FAB auth manager's Azure AD OAuth login defaulted `verify_signature=False` when decoding the ID token, so an attacker able to present a forged or unsigned (`alg:none`) ID token to the OAuth callback could bypass authentication and log in as an arbitrary user, including one holding the Admin role (CWE-347). Deployments running the FAB auth manager with the Azure AD OAuth login path under its default configuration are affected; the Authentik path already defaulted to `True`. This issue affects `apache-airflow-providers-fab` before 3.7.3. Users are advised to upgrade to `apache-airflow-providers-fab` 3.7.3, which defaults `verify_signature=True`.

Severity

9.8 (Critical)


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

SSVC

Exploitation: none Automatable: yes Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-07-29 15:29 UTC

CWE

CWE-347 - Improper Verification of Cryptographic Signature

Assigner

apache CNA under the mitre root

CNA scorecard B 76/100 over 1176 records in the last 180 days details

References

3 references

URL	Tags
https://github.com/apache/airflow/pull/69374	patch
https://lists.apache.org/thread/x4784l7z00tl3gw4t…	vendor-advisory
http://www.openwall.com/lists/oss-security/2026/0…

Impacted products

1 product

Vendor	Product	Version
Apache Software Foundation	Apache Airflow FAB provider	Affected: 0 , < 3.7.3 (semver)

Credits

MalHyuk Jarek Potiuk

Show details on NVD website

JSON

To clipboard

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          "dateUpdated": "2026-07-29T09:02:17.538Z",
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              "baseScore": 9.8,
              "baseSeverity": "CRITICAL",
              "confidentialityImpact": "HIGH",
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              "userInteraction": "NONE",
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                  }
                ],
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                "timestamp": "2026-07-29T15:29:52.670228Z",
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        "providerMetadata": {
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          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
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    "cna": {
      "affected": [
        {
          "collectionURL": "https://pypi.python.org",
          "defaultStatus": "unaffected",
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          "packageURL": "pkg:pypi/apache-airflow-providers-fab",
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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.

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