{"id":9521,"date":"2025-08-01T14:17:56","date_gmt":"2025-08-01T14:17:56","guid":{"rendered":"http:\/\/localhost\/?p=9521"},"modified":"2025-08-01T14:17:56","modified_gmt":"2025-08-01T14:17:56","slug":"webfingerjs-is-vulnerable-to-blind-ssrf-attacks-through-localhost","status":"publish","type":"post","link":"https:\/\/zero.redgem.net\/?p=9521","title":{"rendered":"webfinger.js is vulnerable to Blind SSRF attacks through localhost"},"content":{"rendered":"<div style=\"font-family: Arial, sans-serif; max-width: 1200px; margin: 0 auto;\">\n<h2 style=\"color: #333; border-bottom: 2px solid #ffcc00; padding-bottom: 10px;\">CVE Details<\/h2>\n<div style=\"display: grid; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); gap: 20px; margin-bottom: 20px;\">\n<div style=\"padding: 20px; border-radius: 8px; box-shadow: 0 2px 4px rgba(0,0,0,0.1);\">\n<h3 style=\"margin-top: 0; \">Basic Information<\/h3>\n<table style=\"width:100%; border-collapse: collapse;\">\n<tr>\n<th style=\"text-align: left; padding: 8px; border-bottom: 1px solid #ddd;\">Title<\/th>\n<td style=\"padding: 8px; border-bottom: 1px solid #ddd;\">webfinger.js is vulnerable to Blind SSRF attacks through localhost<\/td>\n<\/tr>\n<tr>\n<th style=\"text-align: left; padding: 8px; border-bottom: 1px solid #ddd;\">Type<\/th>\n<td style=\"padding: 8px; border-bottom: 1px solid #ddd;\">cve<\/td>\n<\/tr>\n<tr>\n<th style=\"text-align: left; padding: 8px; border-bottom: 1px solid #ddd;\">Published<\/th>\n<td style=\"padding: 8px; border-bottom: 1px solid #ddd;\">2025-08-01T18:03:41.619Z<\/td>\n<\/tr>\n<tr>\n<th style=\"text-align: left; padding: 8px; border-bottom: 1px solid #ddd;\">Modified<\/th>\n<td style=\"padding: 8px; border-bottom: 1px solid #ddd;\">2025-08-01T18:39:35.748Z<\/td>\n<\/tr>\n<\/table>\n<\/div>\n<div style=\"padding: 20px; border-radius: 8px; box-shadow: 0 2px 4px rgba(0,0,0,0.1);\">\n<h3 style=\"margin-top: 0; \">Product Information<\/h3>\n<table style=\"width:100%; border-collapse: collapse;\">\n<tr>\n<th style=\"text-align: left; padding: 8px; border-bottom: 1px solid #ddd;\">Vendor<\/th>\n<td style=\"padding: 8px; border-bottom: 1px solid #ddd;\">silverbucket<\/td>\n<\/tr>\n<tr>\n<th style=\"text-align: left; padding: 8px; border-bottom: 1px solid #ddd;\">Product<\/th>\n<td style=\"padding: 8px; border-bottom: 1px solid #ddd;\">webfinger.js<\/td>\n<\/tr>\n<tr>\n<th style=\"text-align: left; padding: 8px; border-bottom: 1px solid #ddd;\">Version<\/th>\n<td style=\"padding: 8px; border-bottom: 1px solid #ddd;\">< 2.8.1<\/td>\n<\/tr>\n<\/table>\n<\/div>\n<\/div>\n<div style=\"padding: 20px; border-radius: 8px; box-shadow: 0 2px 4px rgba(0,0,0,0.1); margin-bottom: 20px;\">\n<h3 style=\"margin-top: 0; \">CVSS Information<\/h3>\n<table style=\"width:100%; border-collapse: collapse;\">\n<tr>\n<th style=\"text-align: left; padding: 8px; border-bottom: 1px solid #ddd;\">Base Score<\/th>\n<td style=\"padding: 8px; border-bottom: 1px solid #ddd; color: #ffcc00; font-weight: bold;\">6.9 (MEDIUM)<\/td>\n<\/tr>\n<tr>\n<th style=\"text-align: left; padding: 8px; border-bottom: 1px solid #ddd;\">Attack Vector<\/th>\n<td style=\"padding: 8px; border-bottom: 1px solid #ddd;\">CVSS:4.0\/AV:N\/AC:L\/AT:N\/PR:N\/UI:N\/VC:L\/VI:N\/VA:N\/SC:N\/SI:N\/SA:N<\/td>\n<\/tr>\n<\/table>\n<\/div>\n<div style=\"padding: 15px; border-radius: 5px; margin-bottom: 20px;\">\n<h4 style=\"margin-top: 0; \">Affected Products<\/h4>\n<ul style=\"margin: 0; padding-left: 20px;\">\n<li>silverbucket webfinger.js < 2.8.1<\/li>\n<\/ul>\n<\/div>\n<div style=\"padding: 20px; border-radius: 8px; box-shadow: 0 2px 4px rgba(0,0,0,0.1); margin-bottom: 20px;\">\n<h3 style=\"margin-top: 0; \">Additional Information<\/h3>\n<table style=\"width:100%; border-collapse: collapse;\">\n<tr>\n<th style=\"text-align: left; padding: 8px; border-bottom: 1px solid #ddd;\">CWE List<\/th>\n<td style=\"padding: 8px; border-bottom: 1px solid #ddd;\">CWE-918<\/td>\n<\/tr>\n<tr>\n<th style=\"text-align: left; padding: 8px; border-bottom: 1px solid #ddd;\">Source<\/th>\n<td style=\"padding: 8px; border-bottom: 1px solid #ddd;\">GitHub_M<\/td>\n<\/tr>\n<\/table>\n<\/div>\n<div style=\"padding: 20px; border-radius: 8px; box-shadow: 0 2px 4px rgba(0,0,0,0.1); margin-bottom: 20px;\">\n<h3 style=\"margin-top: 0; \">Description<\/h3>\n<div style=\"padding: 15px; border-left: 4px solid #4CAF50; \">webfinger.js is a TypeScript-based WebFinger client that runs in both browsers and Node.js environments. In versions 2.8.0 and below, the lookup function accepts user addresses for account checking. However, the ActivityPub specification requires preventing access to localhost services in production. This library does not prevent localhost access, only checking for hosts that start with &#8220;localhost&#8221; and end with a port. Users can exploit this by creating servers that send GET requests with controlled host, path, and port parameters to query services on the instance&#8217;s host or local network, enabling blind SSRF attacks. This is fixed in version 2.8.1.<\/div>\n<\/div>\n<div style=\"padding: 15px; border-radius: 5px; margin-bottom: 20px;\">\n<h4 style=\"margin-top: 0; \">References<\/h4>\n<ul style=\"margin: 0; padding-left: 20px;\">\n<li><a href=\"https:\/\/github.com\/silverbucket\/webfinger.js\/security\/advisories\/GHSA-8xq3-w9fx-74rv\" target=\"_blank\">https:\/\/github.com\/silverbucket\/webfinger.js\/security\/advisories\/GHSA-8xq3-w9fx-74rv<\/a><\/li>\n<li><a href=\"https:\/\/github.com\/silverbucket\/webfinger.js\/commit\/b5f2f2c957297d25f4d76072963fccaee2e3095a\" target=\"_blank\">https:\/\/github.com\/silverbucket\/webfinger.js\/commit\/b5f2f2c957297d25f4d76072963fccaee2e3095a<\/a><\/li>\n<li><a href=\"https:\/\/github.com\/silverbucket\/webfinger.js\/releases\/tag\/v2.8.1\" target=\"_blank\">https:\/\/github.com\/silverbucket\/webfinger.js\/releases\/tag\/v2.8.1<\/a><\/li>\n<\/ul>\n<\/div>\n<div style=\"text-align: center; margin-top: 30px;\">\n<a href=\"\" target=\"_blank\" style=\"display: inline-block; background-color: #4CAF50; color: white; padding: 12px 24px; text-decoration: none; border-radius: 4px; font-weight: bold; transition: background-color 0.3s;\">View Full CVE Details<\/a>\n<\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>CVE Details Basic Information Title webfinger.js is vulnerable to Blind SSRF attacks through localhost Type cve Published 2025-08-01T18:03:41.619Z Modified 2025-08-01T18:39:35.748Z Product Information Vendor silverbucket Product&#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-9521","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 - 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