{"cve":"CVE-2026-2880","nvd":{"published":"2026-02-27T19:16:12.807","modified":"2026-06-17T10:31:56.523","status":"Analyzed","description":"A vulnerability in @fastify/middie versions < 9.2.0 can result in authentication/authorization bypass when using path-scoped middleware (for example, app.use('/secret', auth)).\n\nWhen Fastify router normalization options are enabled (such as ignoreDuplicateSlashes, useSemicolonDelimiter, and related trailing-slash behavior), crafted request paths may bypass middleware checks while still being routed to protected handlers.","cvss_v4":{"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N","score":8.2},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","score":9.1},"cwes":["CWE-20"],"references":["https://github.com/fastify/middie/security/advisories/GHSA-8p85-9qpw-fwgw"],"products":["fastify:fastify\\/middie"],"source":"nvd","synced_at":"2026-10-19T22:24:17.937441719+00:00"},"epss":{"cve":"CVE-2026-2880","score":0.0043,"percentile":0.37227,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-8p85-9qpw-fwgw","url":"https://osv.dev/vulnerability/GHSA-8p85-9qpw-fwgw","summary":"@fastify/middie has Improper Path Normalization when Using Path-Scoped Middleware","modified":"2026-02-28T06:56:21.047235Z","packages":[{"ecosystem":"npm","name":"@fastify/middie","purl":"pkg:npm/%40fastify/middie","ranges":["<9.2.0"],"fixed":["9.2.0"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}