{"id":"CVE-2026-92087","aliases":["EUVD-2026-80788","GHSA-7h52-2rwr-m76r"],"status":"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.","severity":{"version":"3.1","score":8.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-08","score":0.00475,"percentile":0.41301,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-285","CWE-697"],"published":"2026-09-16T14:21:23Z","modified":"2026-10-28T02:30:48Z","products":[{"vendor":"@fastify/auth","product":"@fastify/auth"}],"references":[{"url":"https://github.com/fastify/fastify-auth/security/advisories/GHSA-7h52-2rwr-m76r","tags":["advisory"]},{"url":"https://cna.openjsf.org/security-advisories.html","tags":["advisory"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/92xxx/CVE-2026-92087.json","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-92087","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-92087","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.","status":"published","published":"2026-09-16T14:21:23.686Z","modified":"2026-09-17T19:10:19.438Z","cvss":[{"version":"3.1","score":8.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N","level":"high","assessor":"cna"}],"cwes":["CWE-285","CWE-697"],"updated_at":"2026-11-02T13:48:35.749498Z"}],"euvd":[{"id":"EUVD-2026-80788","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.","status":"published","published":"2026-09-16T14:21:23Z","modified":"2026-09-17T19:10:19Z","cvss":[{"version":"3.1","score":8.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N","level":"high"}],"updated_at":"2026-11-02T17:28:10.042182Z"}],"nvd":[{"id":"CVE-2026-92087","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.","status":"published","published":"2026-09-16T15:18:59.653Z","modified":"2026-09-17T20:18:55.393Z","cvss":[{"version":"3.1","score":8.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N","level":"high","assessor":"secondary"}],"cwes":["CWE-285","CWE-697"],"updated_at":"2026-11-02T14:12:48.630594Z"}],"osv":[{"id":"CVE-2026-92087","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.","status":"published","published":"2026-09-16T14:21:23.686Z","modified":"2026-10-28T02:30:48.31189283Z","cvss":[{"version":"3.1","score":8.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N","level":"high"}],"cwes":["CWE-285","CWE-697"],"updated_at":"2026-11-02T15:45:20.269367Z"}]}}