{"id":"CVE-2026-2880","state":"PUBLISHED","title":"@fastify/middie has an improper path normalization vulnerability","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.","publishedAt":"2026-02-27T18:25:37.428Z","updatedAt":"2026-02-27T18:56:02.979Z","severity":{"score":8.2,"label":"High","version":"4.0","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","source":"openjs"},"assigner":"openjs","products":["@fastify/middie @fastify/middie"],"affected":[{"vendor":"@fastify/middie","product":"@fastify/middie","packageURL":"pkg:npm/@fastify/middie","defaultStatus":"unaffected","versions":[{"version":"0.0.0","status":"affected","lessThan":"9.2.0","versionType":"semver"}]}],"references":["https://github.com/fastify/middie/security/advisories/GHSA-8p85-9qpw-fwgw"],"weaknesses":["CWE-20"],"ingestedAt":"2026-10-29T20:11:31.369Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/2xxx/CVE-2026-2880.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-2880","state":"PUBLISHED","datePublished":"2026-02-27T18:25:37.428Z","dateUpdated":"2026-02-27T18:56:02.979Z","assignerShortName":"openjs","assignerOrgId":"ce714d77-add3-4f53-aff5-83d477b104bb","dateReserved":"2026-02-20T16:50:56.850Z"},"containers":{"cna":{"title":"@fastify/middie has an improper path normalization vulnerability","descriptions":[{"lang":"en","value":"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."}],"affected":[{"vendor":"@fastify/middie","product":"@fastify/middie","packageURL":"pkg:npm/@fastify/middie","defaultStatus":"unaffected","versions":[{"version":"0.0.0","status":"affected","lessThan":"9.2.0","versionType":"semver"}]}],"references":[{"url":"https://github.com/fastify/middie/security/advisories/GHSA-8p85-9qpw-fwgw"}],"metrics":[{"cvssV4_0":{"Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","Safety":"NOT_DEFINED","attackComplexity":"LOW","attackRequirements":"PRESENT","attackVector":"NETWORK","baseScore":8.2,"baseSeverity":"HIGH","exploitMaturity":"NOT_DEFINED","privilegesRequired":"NONE","providerUrgency":"NOT_DEFINED","subAvailabilityImpact":"NONE","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","userInteraction":"NONE","valueDensity":"NOT_DEFINED","vectorString":"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","version":"4.0","vulnAvailabilityImpact":"NONE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"HIGH","vulnerabilityResponseEffort":"NOT_DEFINED"},"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}]}],"problemTypes":[{"descriptions":[{"cweId":"CWE-20","description":"CWE-20","lang":"en","type":"CWE"}]}],"providerMetadata":{"shortName":"openjs","orgId":"ce714d77-add3-4f53-aff5-83d477b104bb","dateUpdated":"2026-02-27T18:25:37.428Z"},"x_generator":{"engine":"cve-kit 0.1.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-02-27T18:55:36.300396Z","id":"CVE-2026-2880","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-02-27T18:56:02.979Z"}}]}}}