{"id":"CVE-2026-92087","title":"@fastify/auth is a Fastify plugin that composes multiple authentication and authorization strategies into a single route guard","summary":"@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…","severity":"high","cvss":8.1,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N","cwe":["CWE-285","CWE-697"],"vendor":"@fastify/auth","product":"@fastify/auth","affected":["@fastify/auth >= 5.0.0 < 5.1.1"],"published":"2026-09-16","updated":"2026-09-17","sourceUpdated":"2026-09-17T20:18:55.393","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-92087","references":[{"url":"https://cna.openjsf.org/security-advisories.html","label":"ce714d77-add3-4f53-aff5-83d477b104bb"},{"url":"https://github.com/fastify/fastify-auth/security/advisories/GHSA-7h52-2rwr-m76r","label":"ce714d77-add3-4f53-aff5-83d477b104bb"}],"tags":["nvd","cve.org"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2026-09-17T19:10:08.336484Z"},"ingestedAt":"2026-09-16T14:57:28.060Z","epss":0.00364,"epssPercentile":0.30088,"slug":"CVE-2026-92087","body":"## Overview\n\n@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.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":45,"depthScoreParts":{"impact":44.6,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}