{"id":29474,"date":"2025-12-08T19:52:07","date_gmt":"2025-12-08T19:52:07","guid":{"rendered":"http:\/\/localhost\/?p=29474"},"modified":"2025-12-08T19:52:07","modified_gmt":"2025-12-08T19:52:07","slug":"traefik-doesnt-prevent-path-normalization-bypass-in-router-middleware-rules","status":"publish","type":"post","link":"https:\/\/zero.redgem.net\/?p=29474","title":{"rendered":"Traefik doesn&#8217;t Prevent Path Normalization Bypass in Router + Middleware Rules_CVE-2025-66490"},"content":{"rendered":"<p>{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;Traefik is an HTTP reverse proxy and load balancer. For versions prior to 2.11.32 and 2.11.31 through 3.6.2, requests using PathPrefix, Path or PathRegex matchers can bypass path normalization. When Traefik uses path-based routing, requests containing URL-encoded restricted characters (\/, \\\\, Null, ;, ?, #) can bypass the middleware chain and reach unintended backends. 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For versions prior to 2.11.32 and 2.11.31 through 3.6.2, requests using PathPrefix, Path or PathRegex matchers&#8230;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[2],"tags":[6,8,48,12,21,13,7,11,5],"class_list":["post-29474","post","type-post","status-publish","format-standard","hentry","category-category_cve","tag-cve","tag-cvss","tag-cvss-69","tag-exploit","tag-medium","tag-news","tag-security","tag-tapic","tag-vulnerability"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.5 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>Traefik doesn&#039;t Prevent Path Normalization Bypass in Router + Middleware Rules_CVE-2025-66490 - zero redgem<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/zero.redgem.net\/?p=29474\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Traefik doesn&#039;t Prevent Path Normalization Bypass in Router + Middleware Rules_CVE-2025-66490 - zero redgem\" \/>\n<meta property=\"og:description\" content=\"{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;Traefik is an HTTP reverse proxy and load balancer. 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