CVE-2026-33978
5.4 · MEDIUMOverview
CVE-2026-33978 is a medium-severity vulnerability affecting streetwriters notesnook_mobile. It was published on April 1, 2026 and has a CVSS 3.1 base score of 5.4 (MEDIUM).
This vulnerability has a CVSS 3.1 base score of 5.4, rated MEDIUM. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical Description
Notesnook is a note-taking app focused on user privacy & 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 </a><img src=x onerror=...>. 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.
Remediation
Check the references section for vendor advisories and patches from streetwriters. Update notesnook_mobile to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| streetwriters | notesnook_mobile | >= 0, < 3.3.17 | Affected |
Frequently Asked Questions
What is CVE-2026-33978?
CVE-2026-33978 is a medium-severity vulnerability affecting streetwriters notesnook_mobile. It was published on April 1, 2026 and has a CVSS 3.1 base score of 5.4 (MEDIUM).
How severe is CVE-2026-33978?
This vulnerability has a CVSS 3.1 base score of 5.4, rated MEDIUM. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2026-33978?
Check the references section for vendor advisories and patches from streetwriters. Update notesnook_mobile to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-33978?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-33978 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
Automated penetration testing that runs continuously, not just quarterly.
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Browser-based exploitation validates findings with real proof-of-concept.
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