CVE-2026-33976

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 page’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.

CVSS v3 9.6 CRITICAL

9.6^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 2.8 / Impact : 6.0

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope CHANGED

References

Link	Resource
https://github.com/streetwriters/notesnook/security/advisories/GHSA-f42f-phvp-43x5	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:streetwriters:notesnook_desktop::::::::
	cpe:2.3:a:streetwriters:notesnook_mobile::::::android::*
	cpe:2.3:a:streetwriters:notesnook_mobile::::::iphone_os::*

History

No history.

Information

Published : 2026-03-27 22:16

Updated : 2026-06-17 10:38

NVD link : CVE-2026-33976

Mitre link : CVE-2026-33976

CVE.ORG link : CVE-2026-33976

JSON object : View

Products Affected

streetwriters

notesnook_desktop
notesnook_mobile

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

CWE-94

Improper Control of Generation of Code ('Code Injection')

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