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MSRC_CVE-2026-32597

Vulnerability from csaf_microsoft - Published: 2026-07-24 01:01 - Updated: 2026-08-08 01:40
Summary
PyJWT accepts unknown `crit` header extensions (RFC 7515 §4.1.11 MUST violation)
Notes
Additional Resources: To determine the support lifecycle for your software, see the Microsoft Support Lifecycle: https://support.microsoft.com/lifecycle
Disclaimer: The information provided in the Microsoft Knowledge Base is provided \"as is\" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.
CVE-2026-32597
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
CWE-345 - Insufficient Verification of Data Authenticity
Affected products
Product Identifier Version Remediation
Unresolved product id: 20159-17084 —
Product Identifier Version Remediation
Unresolved product id: 17084-1 —
Vendor Fix fix
References
To clipboard 

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        "text": "To determine the support lifecycle for your software, see the Microsoft Support Lifecycle: https://support.microsoft.com/lifecycle",
        "title": "Additional Resources"
      },
      {
        "category": "legal_disclaimer",
        "text": "The information provided in the Microsoft Knowledge Base is provided \\\"as is\\\" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.",
        "title": "Disclaimer"
      }
    ],
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      },
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        "url": "https://www.first.org/cvss"
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    ],
    "title": "PyJWT accepts unknown `crit` header extensions (RFC 7515 \u00a74.1.11 MUST violation)",
    "tracking": {
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  "vulnerabilities": [
    {
      "cve": "CVE-2026-32597",
      "cwe": {
        "id": "CWE-345",
        "name": "Insufficient Verification of Data Authenticity"
      },
      "notes": [
        {
          "category": "general",
          "text": "GitHub_M",
          "title": "Assigning CNA"
        }
      ],
      "product_status": {
        "fixed": [
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        ],
        "known_affected": [
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      },
      "references": [
        {
          "category": "self",
          "summary": "CVE-2026-32597 PyJWT accepts unknown `crit` header extensions (RFC 7515 \u00a74.1.11 MUST violation) - VEX",
          "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-32597.json"
        }
      ],
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          "date": "2026-07-24T01:01:44.000Z",
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      ],
      "scores": [
        {
          "cvss_v3": {
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            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 7.5,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "NONE",
            "environmentalScore": 0.0,
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "temporalScore": 7.5,
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N",
            "version": "3.1"
          },
          "products": [
            "17084-1"
          ]
        }
      ],
      "title": "PyJWT accepts unknown `crit` header extensions (RFC 7515 \u00a74.1.11 MUST violation)"
    }
  ]
}



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