{"id":44281,"date":"2026-04-12T03:36:19","date_gmt":"2026-04-12T03:36:19","guid":{"rendered":"http:\/\/localhost\/?p=44281"},"modified":"2026-04-12T03:36:19","modified_gmt":"2026-04-12T03:36:19","slug":"notesnook-stored-xss-in-mobile-share-editor-via-unescaped-web-clip-title-metadata","status":"publish","type":"post","link":"https:\/\/zero.redgem.net\/?p=44281","title":{"rendered":"Notesnook: Stored XSS in mobile share editor via unescaped web clip title metadata_CVE-2026-33978"},"content":{"rendered":"<p>{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;Notesnook is a note-taking app focused on user privacy \\u0026 ease of use. Prior to version 3.3.17, a stored XSS vulnerability exists in the mobile share \/ web clip flow because attacker-controlled clip metadata is concatenated into HTML without escaping and then rendered with innerHTML inside the mobile share editor WebView. An attacker can control the shared title metadata (for example through Android\/iOS share metadata such as TITLE \/ SUBJECT, or through link-preview title data) and inject HTML such as \\u003c\/a\\u003e\\u003cimg src=x onerror=&#8230;\\u003e. When the victim opens the Notesnook share flow and selects Web clip, the payload is inserted into the generated HTML and executed in the mobile editor WebView. This issue has been patched in version 3.3.17.&#8221;,&#8221;published&#8221;:&#8221;2026-04-01T16:11:56.610Z&#8221;,&#8221;modified&#8221;:&#8221;2026-04-01T19:07:24.523Z&#8221;,&#8221;type&#8221;:&#8221;cve&#8221;,&#8221;title&#8221;:&#8221;Notesnook: Stored XSS in mobile share editor via unescaped web clip title metadata&#8221;,&#8221;source&#8221;:&#8221;GitHub_M&#8221;,&#8221;references&#8221;:&#8221;https:\/\/github.com\/streetwriters\/notesnook\/security\/advisories\/GHSA-f27j-fqc6-v7pm\\nhttps:\/\/github.com\/streetwriters\/notesnook\/commit\/fc8807f74db5539036c5e58d3d68a11ea54098db\\nhttps:\/\/github.com\/streetwriters\/notesnook\/releases\/tag\/3.3.17-android&#8221;,&#8221;id&#8221;:&#8221;CVE-2026-33978&#8243;,&#8221;bulletinFamily&#8221;:&#8221;&#8221;,&#8221;cwe&#8221;:[&#8220;CWE-79&#8243;],&#8221;cvelist&#8221;:null,&#8221;sourceData&#8221;:&#8221;streetwriters notesnook \\u003c 3.3.17&#8243;,&#8221;sourceHref&#8221;:&#8221;&#8221;,&#8221;cvss&#8221;:{&#8220;score&#8221;:5.4,&#8221;severity&#8221;:&#8221;MEDIUM&#8221;,&#8221;vector&#8221;:&#8221;CVSS:3.1\/AV:N\/AC:L\/PR:N\/UI:R\/S:U\/C:L\/I:L\/A:N&#8221;,&#8221;version&#8221;:&#8221;3.1&#8243;},&#8221;cvss2&#8243;:{},&#8221;cvss3&#8243;:{&#8220;version&#8221;:&#8221;&#8221;,&#8221;vectorString&#8221;:&#8221;&#8221;,&#8221;baseScore&#8221;:0,&#8221;baseSeverity&#8221;:&#8221;&#8221;,&#8221;attackVector&#8221;:&#8221;&#8221;,&#8221;attackComplexity&#8221;:&#8221;&#8221;,&#8221;privilegesRequired&#8221;:&#8221;&#8221;,&#8221;userInteraction&#8221;:&#8221;&#8221;,&#8221;scope&#8221;:&#8221;&#8221;,&#8221;confidentialityImpact&#8221;:&#8221;&#8221;,&#8221;integrityImpact&#8221;:&#8221;&#8221;,&#8221;availabilityImpact&#8221;:&#8221;&#8221;,&#8221;cvssV3&#8243;:{&#8220;version&#8221;:&#8221;&#8221;,&#8221;vectorString&#8221;:&#8221;&#8221;,&#8221;baseScore&#8221;:0,&#8221;baseSeverity&#8221;:&#8221;&#8221;,&#8221;attackVector&#8221;:&#8221;&#8221;,&#8221;attackComplexity&#8221;:&#8221;&#8221;,&#8221;privilegesRequired&#8221;:&#8221;&#8221;,&#8221;userInteraction&#8221;:&#8221;&#8221;,&#8221;scope&#8221;:&#8221;&#8221;,&#8221;confidentialityImpact&#8221;:&#8221;&#8221;,&#8221;integrityImpact&#8221;:&#8221;&#8221;,&#8221;availabilityImpact&#8221;:&#8221;&#8221;}},&#8221;href&#8221;:&#8221;&#8221;,&#8221;category_name&#8221;:&#8221;CVE&#8221;,&#8221;post_link&#8221;:&#8221;&#8221;,&#8221;product&#8221;:&#8221;notesnook&#8221;,&#8221;version&#8221;:&#8221;\\u003c 3.3.17&#8243;,&#8221;vendor&#8221;:&#8221;streetwriters&#8221;,&#8221;ai_description&#8221;:&#8221;&#8221;,&#8221;ai_severity&#8221;:&#8221;&#8221;,&#8221;ai_vendor&#8221;:&#8221;&#8221;,&#8221;ai_product&#8221;:&#8221;&#8221;,&#8221;ai_version&#8221;:&#8221;&#8221;,&#8221;ai_score&#8221;:0}<\/p>\n","protected":false},"excerpt":{"rendered":"<p>{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;Notesnook is a note-taking app focused on user privacy \\u0026 ease of use. Prior to version 3.3.17, a stored XSS vulnerability exists in the mobile&#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":[6,8,82,12,21,13,7,11,5],"class_list":["post-44281","post","type-post","status-publish","format-standard","hentry","category-category_cve","tag-cve","tag-cvss","tag-cvss-54","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>Notesnook: Stored XSS in mobile share editor via unescaped web clip title metadata_CVE-2026-33978 - 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=44281\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Notesnook: Stored XSS in mobile share editor via unescaped web clip title metadata_CVE-2026-33978 - zero redgem\" \/>\n<meta property=\"og:description\" content=\"{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;Notesnook is a note-taking app focused on user privacy u0026 ease of use. 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