{"id":47555,"date":"2026-04-16T20:51:05","date_gmt":"2026-04-16T20:51:05","guid":{"rendered":"http:\/\/localhost\/?p=47555"},"modified":"2026-04-16T20:51:05","modified_gmt":"2026-04-16T20:51:05","slug":"note-mark-username-enumeration-via-login-endpoint-timing-side-channel","status":"publish","type":"post","link":"https:\/\/zero.redgem.net\/?p=47555","title":{"rendered":"Note Mark: Username Enumeration via Login Endpoint Timing Side-Channel_CVE-2026-40263"},"content":{"rendered":"<p>{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;Note Mark is an open-source note-taking application. In versions 0.19.1 and prior, the login endpoint performs bcrypt password verification only when the supplied username exists, returning immediately for nonexistent usernames. This timing discrepancy allows unauthenticated attackers to enumerate valid usernames by measuring response times, enabling targeted credential attacks. 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In versions 0.19.1 and prior, the login endpoint performs bcrypt password verification only when the supplied username exists,&#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":[6,8,145,12,71,13,7,11,5],"class_list":["post-47555","post","type-post","status-publish","format-standard","hentry","category-category_cve","tag-cve","tag-cvss","tag-cvss-37","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>Note Mark: Username Enumeration via Login Endpoint Timing Side-Channel_CVE-2026-40263 - 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=47555\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Note Mark: Username Enumeration via Login Endpoint Timing Side-Channel_CVE-2026-40263 - zero redgem\" \/>\n<meta property=\"og:description\" content=\"{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;Note Mark is an open-source note-taking application. 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