๐Ÿ” CVE Alert

CVE-2026-33976

CRITICAL 9.7

Notesnook vulnerable to RCE via stored XSS in Web Clipper rendering

CVSS Score
9.7
EPSS Score
0.1%
EPSS Percentile
34th

Notesnook is a note-taking app. Prior to version 3.3.11 on Web/Desktop and 3.3.17 on Android/iOS, a stored XSS in the Web Clipper rendering flow can be escalated to remote code execution in the desktop app. The root cause is that the clipper preserves attacker-controlled attributes from the source pageโ€™s root element and stores them inside web-clip HTML. When the clip is later opened, Notesnook renders that HTML into a same-origin, unsandboxed iframe using `contentDocument.write(...)`. Event-handler attributes such as `onload`, `onclick`, or `onmouseover` execute in the Notesnook origin. In the desktop app, this becomes RCE because Electron is configured with `nodeIntegration: true` and `contextIsolation: false`. Version 3.3.11 Web/Desktop and 3.3.17 on Android/iOS patch the issue.

CWE CWE-79 CWE-94
Vendor streetwriters
Product notesnook web/desktop
Published Mar 27, 2026
Last Updated Apr 3, 2026
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CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
Required
Scope
Changed
Confidentiality
High
Integrity
High
Availability
High

Affected Versions

streetwriters / Notesnook Web/Desktop
< 3.3.11
streetwriters / Notesnook iOS/Android
< 3.3.17

References

NVD โ†— CVE.org โ†— EPSS Data โ†—
github.com: https://github.com/streetwriters/notesnook/security/advisories/GHSA-f42f-phvp-43x5