{"id":81333,"date":"2026-07-01T14:59:20","date_gmt":"2026-07-01T11:29:20","guid":{"rendered":"https:\/\/afaghhosting.net\/blog\/cve-2026-14198-fastify-middie-vulnerable-to-authorization-bypass-via-encoded-slash-in-path-parameter-values\/"},"modified":"2026-07-01T14:59:20","modified_gmt":"2026-07-01T11:29:20","slug":"cve-2026-14198-fastify-middie-vulnerable-to-authorization-bypass-via-encoded-slash-in-path-parameter-values","status":"publish","type":"post","link":"https:\/\/afaghhosting.net\/blog\/cve-2026-14198-fastify-middie-vulnerable-to-authorization-bypass-via-encoded-slash-in-path-parameter-values\/","title":{"rendered":"CVE-2026-14198 &#8211; @fastify\/middie vulnerable to authorization bypass via encoded slash in path parameter values"},"content":{"rendered":"<p>CVE ID :CVE-2026-14198<\/p>\n<p>  Published : July 1, 2026, 11:29 a.m. | 17\u00a0minutes ago<\/p>\n<p>  Description :@fastify\/middie versions 9.1.0 through 9.3.2 decode the encoded slash %2F inside path parameter values before matching middleware paths, while Fastify&#8217;s underlying router preserves the encoding during route lookup. The two layers disagree on the canonical request path, so the middleware fails to match a URL that the route handler does match. When middleware is used for authentication, authorization, rate limiting, or auditing on parameterized paths, an attacker can reach the protected handler by sending a single crafted URL with an encoded slash in the parameter position. The bypass is HTTP method agnostic and requires no authentication or special preconditions. Patches: upgrade to @fastify\/middie 9.3.3. Workarounds: avoid parameterized middleware paths for security decisions, or enforce authentication at the route handler or via a Fastify hook that runs after the router has resolved the request.<\/p>\n<p>  Severity: 9.1 | CRITICAL<\/p>\n<p>  Visit the link for more details, such as CVSS details, affected products, timeline, and more&#8230;\u00a0<\/p>\n","protected":false},"excerpt":{"rendered":"<p>CVE ID :CVE-2026-14198 Published : July 1, 2026, 11:29 a.m. | 17\u00a0minutes ago Description :@fastify\/middie versions 9.1.0 through 9.3.2 decode the encoded slash %2F inside path parameter values before matching middleware paths, while Fastify&#8217;s underlying router preserves the encoding during route lookup. The two layers disagree on the canonical request path, so the middleware fails &hellip;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[26],"tags":[],"class_list":["post-81333","post","type-post","status-publish","format-standard","hentry","category-vulnerability"],"_links":{"self":[{"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/posts\/81333","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/comments?post=81333"}],"version-history":[{"count":0,"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/posts\/81333\/revisions"}],"wp:attachment":[{"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/media?parent=81333"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/categories?post=81333"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/tags?post=81333"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}