{"id":28954,"date":"2025-12-05T17:20:04","date_gmt":"2025-12-05T17:20:04","guid":{"rendered":"http:\/\/localhost\/?p=28954"},"modified":"2025-12-05T17:20:04","modified_gmt":"2025-12-05T17:20:04","slug":"nextcloud-deck-app-allows-to-spoof-file-extensions-by-using-rtlo-characters","status":"publish","type":"post","link":"https:\/\/zero.redgem.net\/?p=28954","title":{"rendered":"Nextcloud Deck app allows to spoof file extensions by using RTLO characters_CVE-2025-66548"},"content":{"rendered":"<p>{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;Nextcloud Deck is a kanban style organization tool aimed at personal planning and project organization for teams integrated with Nextcloud. Prior to 1.12.7, 1.14.4, and 1.15.1, file extension can be spoofed by using RTLO characters, tricking users into download files with a different extension than what is displayed. 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Prior to 1.12.7, 1.14.4, and&#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":[6,8,121,12,71,13,7,11,5],"class_list":["post-28954","post","type-post","status-publish","format-standard","hentry","category-category_cve","tag-cve","tag-cvss","tag-cvss-33","tag-exploit","tag-low","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>Nextcloud Deck app allows to spoof file extensions by using RTLO characters_CVE-2025-66548 - 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=28954\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Nextcloud Deck app allows to spoof file extensions by using RTLO characters_CVE-2025-66548 - zero redgem\" \/>\n<meta property=\"og:description\" content=\"{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;Nextcloud Deck is a kanban style organization tool aimed at personal planning and project organization for teams integrated with Nextcloud. 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