{
  "containers": {
    "cna": {
      "affected": [
        {
          "product": "authlib",
          "vendor": "authlib",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 1.9.0"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Authlib is a Python library which builds OAuth and OpenID Connect servers. Prior to 1.9.0, the default RFC 7523 JWTBearerGrant.get_audiences() returns an empty list, causing JWTBearerGrant.verify_claims() to require only that an aud claim exists without matching the current authorization server. An attacker holding a legitimate assertion for another service can present it to a server that shares the signing key and uses the default grant, obtaining an access token across a trust boundary. Implementations that override get_audiences() with the server\u0027s valid audience identifiers are not affected. This issue is fixed in version 1.9.0."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "HIGH",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 6.8,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "LOW",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-287",
              "description": "CWE-287: Improper Authentication",
              "lang": "en",
              "type": "CWE"
            }
          ]
        },
        {
          "descriptions": [
            {
              "cweId": "CWE-1188",
              "description": "CWE-1188: Insecure Default Initialization of Resource",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-10-22T21:28:37.879Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/authlib/authlib/security/advisories/GHSA-fch4-3c6x-j4gc",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/authlib/authlib/security/advisories/GHSA-fch4-3c6x-j4gc"
        },
        {
          "name": "https://github.com/authlib/authlib/pull/945",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/authlib/authlib/pull/945"
        },
        {
          "name": "https://github.com/authlib/authlib/commit/e3bd41cb29dcfee434453b135ffb487884baeedf",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/authlib/authlib/commit/e3bd41cb29dcfee434453b135ffb487884baeedf"
        },
        {
          "name": "https://github.com/authlib/authlib/releases/tag/v1.9.0",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/authlib/authlib/releases/tag/v1.9.0"
        }
      ],
      "source": {
        "advisory": "GHSA-fch4-3c6x-j4gc",
        "discovery": "UNKNOWN"
      },
      "title": "Authlib: Default JWT bearer grant accepts assertions for the wrong audience"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-114618",
    "datePublished": "2026-10-22T21:28:37.879Z",
    "dateReserved": "2026-10-21T20:34:25.600Z",
    "dateUpdated": "2026-10-22T21:28:37.879Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}