๐Ÿ” CVE Alert

CVE-2026-33978

MEDIUM 5.4

Notesnook: Stored XSS in mobile share editor via unescaped web clip title metadata

CVSS Score
5.4
EPSS Score
0.0%
EPSS Percentile
0th

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.

CWE CWE-79
Vendor streetwriters
Product notesnook
Published Apr 1, 2026
Last Updated Apr 1, 2026
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CVSS v3 Breakdown

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

Affected Versions

streetwriters / notesnook
< 3.3.17

References

NVD โ†— CVE.org โ†— EPSS Data โ†—
github.com: https://github.com/streetwriters/notesnook/security/advisories/GHSA-f27j-fqc6-v7pm github.com: https://github.com/streetwriters/notesnook/commit/fc8807f74db5539036c5e58d3d68a11ea54098db github.com: https://github.com/streetwriters/notesnook/releases/tag/3.3.17-android