{
  "containers": {
    "cna": {
      "affected": [
        {
          "product": "authlib",
          "vendor": "authlib",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 1.9.1"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Authlib is a Python library which builds OAuth and OpenID Connect servers. Prior to 1.9.1, Authlib\u0027s OctKey.import_key() and HMAC signing and verification path accept zero-length key material. If an application\u0027s secret lookup can return an empty string or empty bytes, a remote attacker can compute the deterministic HS256, HS384, or HS512 signature for arbitrary token claims and have Authlib treat the token as authentic. This issue is fixed in version 1.9.1."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "HIGH",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 7.4,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/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-326",
              "description": "CWE-326: Inadequate Encryption Strength",
              "lang": "en",
              "type": "CWE"
            }
          ]
        },
        {
          "descriptions": [
            {
              "cweId": "CWE-1391",
              "description": "CWE-1391: Use of Weak Credentials",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-10-22T21:14:03.060Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/authlib/authlib/security/advisories/GHSA-8m4g-j4wp-wgcg",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/authlib/authlib/security/advisories/GHSA-8m4g-j4wp-wgcg"
        },
        {
          "name": "https://github.com/authlib/authlib/commit/4ff30db442c70e29486e1982cb0ad37c037f5f4b",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/authlib/authlib/commit/4ff30db442c70e29486e1982cb0ad37c037f5f4b"
        },
        {
          "name": "https://github.com/authlib/authlib/releases/tag/v1.9.1",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/authlib/authlib/releases/tag/v1.9.1"
        }
      ],
      "source": {
        "advisory": "GHSA-8m4g-j4wp-wgcg",
        "discovery": "UNKNOWN"
      },
      "title": "Authlib accepts an empty HMAC key, allowing JWS/JWT signature forgery (HS256/HS384/HS512)"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-114616",
    "datePublished": "2026-10-22T21:14:03.060Z",
    "dateReserved": "2026-10-21T20:34:25.600Z",
    "dateUpdated": "2026-10-22T21:14:03.060Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}