{"id":52681,"date":"2026-05-08T23:13:52","date_gmt":"2026-05-08T23:13:52","guid":{"rendered":"https:\/\/zero.redgem.net\/?p=52681"},"modified":"2026-05-08T23:13:52","modified_gmt":"2026-05-08T23:13:52","slug":"kirby-system-api-endpoint-leaks-license-data-and-installed-version-to-authenticated-users","status":"publish","type":"post","link":"https:\/\/zero.redgem.net\/?p=52681","title":{"rendered":"Kirby: System API endpoint leaks license data and installed version to authenticated users_CVE-2026-42051"},"content":{"rendered":"<p>{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;Kirby is an open-source content management system. Prior to versions 4.9.0 and 5.4.0, the system API endpoint leaks license data and installed version to authenticated users. 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Prior to versions 4.9.0 and 5.4.0, the system API endpoint leaks license data and installed version to authenticated&#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":[6,8,22,12,21,13,7,11,5],"class_list":["post-52681","post","type-post","status-publish","format-standard","hentry","category-category_cve","tag-cve","tag-cvss","tag-cvss-53","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>Kirby: System API endpoint leaks license data and installed version to authenticated users_CVE-2026-42051 - 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=52681\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Kirby: System API endpoint leaks license data and installed version to authenticated users_CVE-2026-42051 - zero redgem\" \/>\n<meta property=\"og:description\" content=\"{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;Kirby is an open-source content management system. 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