{"id":"CVE-2026-107162","title":"Express Gateway through 1.16.11 contains an authentication bypass vulnerability in the OAuth 2.0 refresh_token grant that fails to validate the token secret or issuing client","summary":"Express Gateway through 1.16.11 contains an authentication bypass vulnerability in the OAuth 2.0 refresh_token grant that fails to validate the token secret or issuing client. Attackers with any valid client credentials and the identifie…","severity":"medium","cvss":6.8,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N","cwe":["CWE-287"],"vendor":"ExpressGateway","product":"express-gateway","affected":["express-gateway <= 1.16.11"],"published":"2026-10-07","updated":"2026-10-07","sourceUpdated":"2026-10-07T13:17:19.963","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-107162","references":[{"url":"https://github.com/ExpressGateway/express-gateway","label":"disclosure@vulncheck.com"},{"url":"https://github.com/ExpressGateway/express-gateway/blob/45612814d12f65889ef3bdf80b2ed7ab9b557736/lib/policies/oauth2/oauth2-server.js#L221-L247","label":"disclosure@vulncheck.com"},{"url":"https://github.com/ExpressGateway/express-gateway/blob/45612814d12f65889ef3bdf80b2ed7ab9b557736/lib/services/tokens/token.service.js#L100-L136","label":"disclosure@vulncheck.com"},{"url":"https://github.com/ExpressGateway/express-gateway/issues/1076","label":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/express-gateway-through-1.16.11-oauth-2.0-refresh-token-validation-bypass","label":"disclosure@vulncheck.com"}],"tags":["nvd","cve.org"],"ingestedAt":"2026-10-07T13:31:04.597Z","slug":"CVE-2026-107162","body":"## Overview\n\nExpress Gateway through 1.16.11 contains an authentication bypass vulnerability in the OAuth 2.0 refresh_token grant that fails to validate the token secret or issuing client. Attackers with any valid client credentials and the identifier portion of another user's refresh token can obtain that user's access token and impersonate them against oauth2-protected APIs.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":37,"depthScoreParts":{"impact":37.4,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}