CVE-2026-114618 (GCVE-0-2026-114618)

Vulnerability from cvelistv5 – Published: 2026-10-22 21:28 – Updated: 2026-10-22 21:28
VLAI
Title
Authlib: Default JWT bearer grant accepts assertions for the wrong audience
Summary
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's valid audience identifiers are not affected. This issue is fixed in version 1.9.0.
Severity
6.8 (Medium)
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N
CWE
  • CWE-287 - Improper Authentication
  • CWE-1188 - Insecure Default Initialization of Resource
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7664 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
authlib authlib Affected: < 1.9.0
guessed Create a notification for this product.
Show details on NVD website
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        }
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      },
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          "url": "https://github.com/authlib/authlib/security/advisories/GHSA-fch4-3c6x-j4gc"
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      "source": {
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        "discovery": "UNKNOWN"
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      "title": "Authlib: Default JWT bearer grant accepts assertions for the wrong audience"
    }
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    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-114618",
    "datePublished": "2026-10-22T21:28:37.879Z",
    "dateReserved": "2026-10-21T20:34:25.600Z",
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                  {
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        "descriptions": [
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          }
        ],
        "id": "CVE-2026-114618",
        "lastModified": "2026-10-22T22:18:04.747",
        "metrics": {
          "cvssMetricV31": [
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              "cvssData": {
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          },
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            "url": "https://github.com/authlib/authlib/pull/945"
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            "source": "security-advisories@github.com",
            "url": "https://github.com/authlib/authlib/releases/tag/v1.9.0"
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          {
            "source": "security-advisories@github.com",
            "url": "https://github.com/authlib/authlib/security/advisories/GHSA-fch4-3c6x-j4gc"
          }
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        "vulnStatus": "Received",
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                "value": "CWE-287"
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    "redhat_vex": {
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      "current_release_date": "2026-10-23T00:35:43+00:00",
      "cve": "CVE-2026-114618",
      "id": "CVE-2026-114618",
      "initial_release_date": "2026-10-22T21:28:37.879000+00:00",
      "product_status:known_affected": "11",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "authlib: Authlib: Unauthorized access via improper JWT audience validation",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-114618.json",
      "version": "3"
    }
  }
}



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