{"id":"CVE-2026-114618","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-114618","generatedAt":"2026-10-28T03:42:02.219Z","title":"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.","description":"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.","published":"2026-10-22T22:18:05.000Z","lastModified":"2026-10-23T19:34:14.000Z","status":"Undergoing Analysis","sourceIdentifier":"security-advisories@github.com","cvss":{"version":"3.1","score":6.8,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N"},"cwe":["CWE-287","CWE-1188"],"affected":[],"epss":{"score":0.00225,"percentile":0.131,"date":"2026-10-27","history":[{"date":"2026-10-23","score":0.00225,"percentile":0.1243}]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (0.22%). Track it; it rarely justifies an emergency change on its own."},"changes":[{"kind":"new","label":"New CVE","at":"2026-10-22T22:18:05.000Z","detail":{"score":"6.8","severity":"MEDIUM","publishedAt":"2026-10-22T22:18:04.747Z"},"summary":"New CVE, medium severity (CVSS 6.8)."}],"references":[{"url":"https://github.com/authlib/authlib/commit/e3bd41cb29dcfee434453b135ffb487884baeedf","source":"security-advisories@github.com"},{"url":"https://github.com/authlib/authlib/pull/945","source":"security-advisories@github.com"},{"url":"https://github.com/authlib/authlib/releases/tag/v1.9.0","source":"security-advisories@github.com"},{"url":"https://github.com/authlib/authlib/security/advisories/GHSA-fch4-3c6x-j4gc","source":"security-advisories@github.com"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-114618","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}