{"id":15584,"date":"2025-09-03T08:46:41","date_gmt":"2025-09-03T08:46:41","guid":{"rendered":"http:\/\/localhost\/?p=15584"},"modified":"2025-09-03T08:46:41","modified_gmt":"2025-09-03T08:46:41","slug":"libsoup-improper-handling-of-http-vary-header-in-libsoup-caching","status":"publish","type":"post","link":"https:\/\/zero.redgem.net\/?p=15584","title":{"rendered":"Libsoup: improper handling of http vary header in libsoup caching_CVE-2025-9901"},"content":{"rendered":"<p>{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;A flaw was found in libsoup\u2019s caching mechanism, SoupCache, where the HTTP Vary header is ignored when evaluating cached responses. This header ensures that responses vary appropriately based on request headers such as language or authentication. Without this check, cached content can be incorrectly reused across different requests, potentially exposing sensitive user information. 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This header ensures that responses&#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":[6,8,97,12,21,13,7,11,5],"class_list":["post-15584","post","type-post","status-publish","format-standard","hentry","category-category_cve","tag-cve","tag-cvss","tag-cvss-59","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>Libsoup: improper handling of http vary header in libsoup caching_CVE-2025-9901 - 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=15584\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Libsoup: improper handling of http vary header in libsoup caching_CVE-2025-9901 - zero redgem\" \/>\n<meta property=\"og:description\" content=\"{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;A flaw was found in libsoup\u2019s caching mechanism, SoupCache, where the HTTP Vary header is ignored when evaluating cached responses. 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