CVE-2026-33955

Notesnook is a note-taking app. Prior to version 3.3.11 on Web/Desktop, a cross-site scripting vulnerability stored in the note history comparison viewer can escalate to remote code execution in a desktop application. The issue is triggered when an attacker-controlled note header is displayed using dangerouslySetInnerHTML without secure handling. When combined with the full backup and restore feature in the desktop application, this becomes remote code execution because Electron is configured with nodeIntegration: true and contextIsolation: false. Version 3.3.11 patches the issue.