{"id":22622,"date":"2025-10-21T18:33:54","date_gmt":"2025-10-21T18:33:54","guid":{"rendered":"http:\/\/localhost\/?p=22622"},"modified":"2025-10-21T18:33:54","modified_gmt":"2025-10-21T18:33:54","slug":"koa-vulnerable-to-open-redirect-via-trailing-double-slash-in-back-redirect-logic","status":"publish","type":"post","link":"https:\/\/zero.redgem.net\/?p=22622","title":{"rendered":"Koa Vulnerable to Open Redirect via Trailing Double-Slash (\/\/) in back Redirect Logic_CVE-2025-62595"},"content":{"rendered":"<p>{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;Koa is expressive middleware for Node.js using ES2017 async functions. In versions 2.16.2 to before 2.16.3 and 3.0.1 to before 3.0.3, a bypass to CVE-2025-8129 was discovered in the Koa.js framework affecting its back redirect functionality. In certain circumstances, an attacker can manipulate the Referer header to force a user\u2019s browser to navigate to an external, potentially malicious website. 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In versions 2.16.2 to before 2.16.3 and 3.0.1 to before 3.0.3, a bypass to CVE-2025-8129&#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":[6,8,123,12,21,13,7,11,5],"class_list":["post-22622","post","type-post","status-publish","format-standard","hentry","category-category_cve","tag-cve","tag-cvss","tag-cvss-43","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>Koa Vulnerable to Open Redirect via Trailing Double-Slash (\/\/) in back Redirect Logic_CVE-2025-62595 - 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=22622\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Koa Vulnerable to Open Redirect via Trailing Double-Slash (\/\/) in back Redirect Logic_CVE-2025-62595 - zero redgem\" \/>\n<meta property=\"og:description\" content=\"{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;Koa is expressive middleware for Node.js using ES2017 async functions. 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