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TI-2026-24428 Aliases CVE-2026-31876

Notesnook has Stored XSS via unsanitized Twitter/X embed URL in editor (`tweetToEmbed`)

Priority LOW 24CWE-79Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
Required
Attack complexity
Low
Impact type
Cross-site scripting
Confidentiality · integrity · availability
Low · Low · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-79.

Summary

Notesnook is a note-taking app focused on user privacy & ease of use. Prior to 3.3.9, a Stored Cross-Site Scripting (XSS) vulnerability existed in Notesnook's editor embed component when rendering Twitter/X embed URLs. The tweetToEmbed() function in component.tsx interpolated the user-supplied URL directly into an HTML string without escaping, which was then assigned to the srcdoc attribute of an <iframe>. This vulnerability is fixed in 3.3.9.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00205 10th percentileScored 2026-11-07
Fix Fixed notesnook (streetwriters): 3.3.9

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
streetwritersnotesnookbefore 3.3.93.3.9Patch availableCNA
  • notesnook Vendorstreetwriters Affected before 3.3.9 Fixed in 3.3.9 Patch available CNA

CPE configurations NVD · 3

CPEVersionsRoleVendor
cpe:2.3:a:streetwriters:notesnook_desktop:*:*:*:*:*:*:*:*before 3.3.9Vulnerablestreetwriters
cpe:2.3:a:streetwriters:notesnook_mobile:*:*:*:*:*:android:*:*before 3.3.15Vulnerablestreetwriters
cpe:2.3:a:streetwriters:notesnook_mobile:*:*:*:*:*:iphone_os:*:*before 3.3.15Vulnerablestreetwriters
  • cpe:2.3:a:streetwriters:notesnook_desktop:*:*:*:*:*:*:*:* Versions before 3.3.9 Vulnerable ·streetwriters
  • cpe:2.3:a:streetwriters:notesnook_mobile:*:*:*:*:*:android:*:* Versions before 3.3.15 Vulnerable ·streetwriters
  • cpe:2.3:a:streetwriters:notesnook_mobile:*:*:*:*:*:iphone_os:*:* Versions before 3.3.15 Vulnerable ·streetwriters

Remediation

  • Fix · CNA notesnook (streetwriters) Fixed in 3.3.9

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-31876

References

Patch 1

Advisory 1

  • TI-2026-26317 Notesnook vulnerable to RCE via stored XSS in Web Clipper rendering CVSS 3.1CRITICAL 9.7
  • TI-2026-26305 Notesnook vulnerable to RCE via stored XSS in Note History diff viewer CVSS 3.1HIGH 8.6
  • TI-2026-30458 Notesnook: RCE via stored XSS in note export rendering CVSS 3.1CRITICAL 9.6

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences