{"id":"CVE-2026-92087","state":"PUBLISHED","title":"@fastify/auth vulnerable to Authorization Bypass via order-dependent evaluation of composed auth","description":"@fastify/auth is a Fastify plugin that composes multiple authentication and authorization strategies into a single route guard. In versions 5.0.0 through 5.1.0, when strategies are composed with the relation \"or\" option together with the run \"all\" option and one entry is a nested array acting as an AND group, the group is evaluated in an order-dependent way: an earlier failing check is silently dropped and the group's result becomes the outcome of its last check. As a result, a request that satisfies only the last member of an AND group, for example an attacker who holds a valid API key but is not an administrator, is authorized instead of rejected, and a related order-dependent bypass affects the mirror configuration where the top-level relation is \"and\" and a nested group uses \"or\". The issue is fixed in @fastify/auth 5.1.1, and users should upgrade to 5.1.1 or later. As a workaround, omit the run \"all\" option where it is not required, order each AND group so its stricter check is evaluated last, or replace nested AND groups with an explicit top-level \"and\" composition.","publishedAt":"2026-09-16T14:21:23.686Z","updatedAt":"2026-09-17T19:10:19.438Z","severity":{"score":8.1,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N","source":"openjs"},"assigner":"openjs","products":["@fastify/auth @fastify/auth"],"affected":[{"vendor":"@fastify/auth","product":"@fastify/auth","packageURL":"pkg:npm/@fastify/auth","defaultStatus":"unaffected","versions":[{"version":"5.0.0","status":"affected","lessThan":"5.1.1","versionType":"semver"},{"version":"5.1.1","status":"unaffected","versionType":"semver"}]}],"references":["https://github.com/fastify/fastify-auth/security/advisories/GHSA-7h52-2rwr-m76r","https://cna.openjsf.org/security-advisories.html"],"weaknesses":["CWE-285","CWE-697"],"ingestedAt":"2026-10-29T20:13:34.582Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/92xxx/CVE-2026-92087.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-92087","state":"PUBLISHED","datePublished":"2026-09-16T14:21:23.686Z","dateUpdated":"2026-09-17T19:10:19.438Z","assignerShortName":"openjs","assignerOrgId":"ce714d77-add3-4f53-aff5-83d477b104bb","dateReserved":"2026-09-15T13:56:18.212Z"},"containers":{"cna":{"title":"@fastify/auth vulnerable to Authorization Bypass via order-dependent evaluation of composed auth","descriptions":[{"lang":"en","value":"@fastify/auth is a Fastify plugin that composes multiple authentication and authorization strategies into a single route guard. In versions 5.0.0 through 5.1.0, when strategies are composed with the relation \"or\" option together with the run \"all\" option and one entry is a nested array acting as an AND group, the group is evaluated in an order-dependent way: an earlier failing check is silently dropped and the group's result becomes the outcome of its last check. As a result, a request that satisfies only the last member of an AND group, for example an attacker who holds a valid API key but is not an administrator, is authorized instead of rejected, and a related order-dependent bypass affects the mirror configuration where the top-level relation is \"and\" and a nested group uses \"or\". The issue is fixed in @fastify/auth 5.1.1, and users should upgrade to 5.1.1 or later. As a workaround, omit the run \"all\" option where it is not required, order each AND group so its stricter check is evaluated last, or replace nested AND groups with an explicit top-level \"and\" composition."}],"affected":[{"vendor":"@fastify/auth","product":"@fastify/auth","packageURL":"pkg:npm/@fastify/auth","defaultStatus":"unaffected","versions":[{"version":"5.0.0","status":"affected","lessThan":"5.1.1","versionType":"semver"},{"version":"5.1.1","status":"unaffected","versionType":"semver"}]}],"references":[{"url":"https://github.com/fastify/fastify-auth/security/advisories/GHSA-7h52-2rwr-m76r"},{"url":"https://cna.openjsf.org/security-advisories.html"}],"metrics":[{"format":"CVSS","cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N","baseScore":8.1,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"GENERAL"}]}],"problemTypes":[{"descriptions":[{"cweId":"CWE-285","lang":"en","description":"CWE-285: Improper Authorization","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-697","lang":"en","description":"CWE-697: Incorrect Comparison","type":"CWE"}]}],"providerMetadata":{"shortName":"openjs","orgId":"ce714d77-add3-4f53-aff5-83d477b104bb","dateUpdated":"2026-09-16T14:21:23.686Z"},"credits":[{"lang":"en","type":"reporter","value":"Sengtocxoen"},{"lang":"en","type":"remediation developer","value":"UlisesGascon"},{"lang":"en","type":"remediation reviewer","value":"mcollina"}],"x_generator":{"engine":"cve-kit 1.0.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-09-17T19:10:08.336484Z","id":"CVE-2026-92087","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":"2026-09-17T19:10:19.438Z"}}]}}}