FKIE_CVE-2026-101918

Vulnerability from fkie_nvd - Published: 2026-09-28 21:17 - Updated: 2026-09-30 19:38
Severity
5.3 (Medium) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Summary
PyJWT is a Python implementation of JSON Web Token standards. From 2.0.0a1 until 2.15.0, PyJWT PyJWKClient.get_signing_key_from_jwt is affected because payload parser catches ValueError but not RecursionError. This occurs when an attacker-controlled recursively nested payload reaches json.loads. As a result, documented PyJWT exception handling does not contain the failure. Consequently, an unauthenticated request can raise an exception that may produce an HTTP 500 response. The advisory-defined affected implementation also includes jwt/api_jwt.py, verify_signature=False. This issue is fixed in version 2.15.0.
References
security-advisories@github.comhttps://github.com/jpadilla/pyjwt/commit/5fde08a6cf906aa7698de2d6391d88b73006b17b
security-advisories@github.comhttps://github.com/jpadilla/pyjwt/releases/tag/2.15.0
security-advisories@github.comhttps://github.com/jpadilla/pyjwt/security/advisories/GHSA-42vr-xj54-vc7v
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "pyjwt",
          "vendor": "jpadilla",
          "versions": [
            {
              "status": "affected",
              "version": "\u003e= 2.0.0a1, \u003c 2.15.0"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "PyJWT is a Python implementation of JSON Web Token standards. From 2.0.0a1 until 2.15.0, PyJWT PyJWKClient.get_signing_key_from_jwt is affected because payload parser catches ValueError but not RecursionError. This occurs when an attacker-controlled recursively nested payload reaches json.loads. As a result, documented PyJWT exception handling does not contain the failure. Consequently, an unauthenticated request can raise an exception that may produce an HTTP 500 response. The advisory-defined affected implementation also includes jwt/api_jwt.py, verify_signature=False. This issue is fixed in version 2.15.0."
    }
  ],
  "id": "CVE-2026-101918",
  "lastModified": "2026-09-30T19:38:27.293",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "LOW",
          "baseScore": 5.3,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 1.4,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-101918",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-09-29T13:55:59.459735Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-09-28T21:17:13.410",
  "references": [
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/jpadilla/pyjwt/commit/5fde08a6cf906aa7698de2d6391d88b73006b17b"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/jpadilla/pyjwt/releases/tag/2.15.0"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/jpadilla/pyjwt/security/advisories/GHSA-42vr-xj54-vc7v"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Awaiting Analysis",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-248"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Secondary"
    }
  ]
}



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