CVE-2026-42090

Published: Mag 04, 2026 Last Modified: Mag 04, 2026
ExploitDB:
Other exploit source:
Google Dorks:
CRITICAL 9,6
Attack Vector: network
Attack Complexity: low
Privileges Required: none
User Interaction: required
Scope: changed
Confidentiality: high
Integrity: high
Availability: high

Description

AI Translation Available

Notesnook is a note-taking app focused on user privacy & ease of use. Prior to Notesnook Web/Desktop version 3.3.15 and prior to Notesnook iOS/Android version 3.3.20, a stored XSS vulnerability in the note export flow can be escalated to remote code execution in the desktop app. The root cause is that exported note fields such as title, headline, and content are inserted into the generated HTML template without HTML escaping. When the note is later exported to PDF, Notesnook renders that HTML into a same-origin, unsandboxed iframe using iframe.srcdoc = .... Injected script executes in the Notesnook origin. In the desktop app, this becomes RCE because Electron is configured with nodeIntegration: true and contextIsolation: false. This issue has been patched in Notesnook Web/Desktop version 3.3.15 and Notesnook iOS/Android version 3.3.20.

79

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

Stable
Common Consequences
Security Scopes Affected:
Access Control Confidentiality Integrity Availability
Potential Impacts:
Bypass Protection Mechanism Read Application Data Execute Unauthorized Code Or Commands
Applicable Platforms
Technologies: AI/ML, Web Based, Web Server
View CWE Details
94

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

Draft
Common Consequences
Security Scopes Affected:
Access Control Integrity Confidentiality Availability Non-Repudiation
Potential Impacts:
Bypass Protection Mechanism Gain Privileges Or Assume Identity Execute Unauthorized Code Or Commands Hide Activities
Applicable Platforms
Languages: Interpreted
Technologies: AI/ML
View CWE Details
https://github.com/streetwriters/notesnook/releases/tag/3.3.20-android
https://github.com/streetwriters/notesnook/releases/tag/v3.3.15
https://github.com/streetwriters/notesnook/security/advisories/GHSA-fjm8-jg78-8…