{"id":39149,"date":"2026-02-04T16:58:24","date_gmt":"2026-02-04T16:58:24","guid":{"rendered":"http:\/\/localhost\/?p=39149"},"modified":"2026-02-04T16:58:24","modified_gmt":"2026-02-04T16:58:24","slug":"siyuan-has-arbitrary-file-write-via-apifilecopyfile-leading-to-rce","status":"publish","type":"post","link":"https:\/\/zero.redgem.net\/?p=39149","title":{"rendered":"SiYuan has Arbitrary File Write via \/api\/file\/copyFile leading to RCE_CVE-2026-25539"},"content":{"rendered":"<p>{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;SiYuan is a personal knowledge management system. Prior to version 3.5.5, the \/api\/file\/copyFile endpoint does not validate the dest parameter, allowing authenticated users to write files to arbitrary locations on the filesystem. This can lead to Remote Code Execution (RCE) by writing to sensitive locations such as cron jobs, SSH authorized_keys, or shell configuration files. 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Prior to version 3.5.5, the \/api\/file\/copyFile endpoint does not validate the dest parameter, allowing authenticated users to write&#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":[9,6,8,10,12,13,7,11,5],"class_list":["post-39149","post","type-post","status-publish","format-standard","hentry","category-category_cve","tag-critical","tag-cve","tag-cvss","tag-cvss-91","tag-exploit","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>SiYuan has Arbitrary File Write via \/api\/file\/copyFile leading to RCE_CVE-2026-25539 - 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=39149\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"SiYuan has Arbitrary File Write via \/api\/file\/copyFile leading to RCE_CVE-2026-25539 - zero redgem\" \/>\n<meta property=\"og:description\" content=\"{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;SiYuan is a personal knowledge management system. 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