{"id":"CVE-2026-116672","state":"PUBLISHED","title":"Authlib RFC 7592 examples omit registration-access-token client binding","description":"Authlib is a Python library which builds OAuth and OpenID Connect servers. From 0.15 until 1.9.1, the documented ClientConfigurationEndpoint.authenticate_client and ClientConfigurationEndpoint.check_permission reference implementations look up a target client from request-controlled client_id data and check only whether that target is editable, without verifying that request.credential belongs to the target client. Deployments following both examples can allow a client holding any valid registration access token to read, modify, or delete another client's registration. Changing redirect_uris can enable authorization code or token interception, while deleting registrations can deny service to affected clients. This issue is fixed in version 1.9.1.","publishedAt":"2026-10-27T16:31:48.429Z","updatedAt":"2026-10-30T20:15:42.022Z","severity":{"score":8.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","source":"GitHub_M"},"assigner":"GitHub_M","products":["authlib authlib"],"affected":[{"vendor":"authlib","product":"authlib","versions":[{"version":">= 0.15, < 1.9.1","status":"affected"}]}],"references":["https://github.com/authlib/authlib/security/advisories/GHSA-c73q-w75p-j82v","https://github.com/authlib/authlib/commit/1bd2a313492ce0a4d0571c150730907aa3fc91ff","https://github.com/authlib/authlib/releases/tag/v1.9.1"],"weaknesses":["CWE-639","CWE-1188"],"ingestedAt":"2026-10-30T20:20:07.083Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/116xxx/CVE-2026-116672.json","commit":"00b08630266947671d4e9b6c8d071b69dbb66e11","baselineCommit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-116672","state":"PUBLISHED","datePublished":"2026-10-27T16:31:48.429Z","dateUpdated":"2026-10-30T20:15:42.022Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-10-26T20:00:59.828Z"},"containers":{"cna":{"title":"Authlib RFC 7592 examples omit registration-access-token client binding","descriptions":[{"lang":"en","value":"Authlib is a Python library which builds OAuth and OpenID Connect servers. From 0.15 until 1.9.1, the documented ClientConfigurationEndpoint.authenticate_client and ClientConfigurationEndpoint.check_permission reference implementations look up a target client from request-controlled client_id data and check only whether that target is editable, without verifying that request.credential belongs to the target client. Deployments following both examples can allow a client holding any valid registration access token to read, modify, or delete another client's registration. Changing redirect_uris can enable authorization code or token interception, while deleting registrations can deny service to affected clients. This issue is fixed in version 1.9.1."}],"affected":[{"vendor":"authlib","product":"authlib","versions":[{"version":">= 0.15, < 1.9.1","status":"affected"}]}],"references":[{"url":"https://github.com/authlib/authlib/security/advisories/GHSA-c73q-w75p-j82v","name":"https://github.com/authlib/authlib/security/advisories/GHSA-c73q-w75p-j82v","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/authlib/authlib/commit/1bd2a313492ce0a4d0571c150730907aa3fc91ff","name":"https://github.com/authlib/authlib/commit/1bd2a313492ce0a4d0571c150730907aa3fc91ff","tags":["x_refsource_MISC"]},{"url":"https://github.com/authlib/authlib/releases/tag/v1.9.1","name":"https://github.com/authlib/authlib/releases/tag/v1.9.1","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":8.8,"baseSeverity":"HIGH","confidentialityImpact":"HIGH","integrityImpact":"HIGH","privilegesRequired":"LOW","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-639","lang":"en","description":"CWE-639: Authorization Bypass Through User-Controlled Key","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-1188","lang":"en","description":"CWE-1188: Insecure Default Initialization of Resource","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-10-27T16:31:48.429Z"},"source":{"advisory":"GHSA-c73q-w75p-j82v","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-10-30T20:15:27.934489Z","id":"CVE-2026-116672","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-30T20:15:42.022Z"}}]}}}