{"id":34549,"date":"2026-01-07T17:47:26","date_gmt":"2026-01-07T17:47:26","guid":{"rendered":"http:\/\/localhost\/?p=34549"},"modified":"2026-01-07T17:47:26","modified_gmt":"2026-01-07T17:47:26","slug":"mailpit-proxy-endpoint-is-vulnerable-to-server-side-request-forgery-ssrf","status":"publish","type":"post","link":"https:\/\/zero.redgem.net\/?p=34549","title":{"rendered":"Mailpit Proxy Endpoint is Vulnerable to Server-Side Request Forgery (SSRF)_CVE-2026-21859"},"content":{"rendered":"<p>{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;Mailpit is an email testing tool and API for developers. Versions 1.28.0 and below have a Server-Side Request Forgery (SSRF) vulnerability in the \/proxy endpoint, allowing attackers to make requests to internal network resources. The \/proxy endpoint validates http:\/\/ and https:\/\/ schemes, but it does not block internal IP addresses, enabling attackers to access internal services and APIs. This vulnerability is limited to HTTP GET requests with minimal headers. 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Versions 1.28.0 and below have a Server-Side Request Forgery (SSRF) vulnerability in the \/proxy endpoint,&#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":[6,8,90,12,21,13,7,11,5],"class_list":["post-34549","post","type-post","status-publish","format-standard","hentry","category-category_cve","tag-cve","tag-cvss","tag-cvss-58","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>Mailpit Proxy Endpoint is Vulnerable to Server-Side Request Forgery (SSRF)_CVE-2026-21859 - 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=34549\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Mailpit Proxy Endpoint is Vulnerable to Server-Side Request Forgery (SSRF)_CVE-2026-21859 - zero redgem\" \/>\n<meta property=\"og:description\" content=\"{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;Mailpit is an email testing tool and API for developers. 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