CVE-2026-31876

Name: CVE-2026-31876
Creator: NVD / NIST
Published: 2026-03-11T19:16:04.14+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 5.4/10EPSS 0.17%

Last modified Jun 17, 2026

CVE-2026-31876 is a medium-severity vulnerability rated 5.4/10 on the CVSS scale. 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. EPSS estimates a 0.17% chance of exploitation in the next 30 days.

Description

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.

Metrics

CVSS 3.1

5.4/10

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

EPSS Probability

0.17%

6.8th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-79

Affected Software

Vendor	Product	Versions
Streetwriters	Notesnook Desktop	< 3.3.9
Streetwriters	Notesnook Mobile	< 3.3.15

References

Timeline

Published: Mar 11, 2026
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2026-31876?

How severe is CVE-2026-31876?

CVE-2026-31876 has a CVSS score of 5.4/10 (MEDIUM severity). The EPSS model estimates a 0.17% probability of exploitation in the next 30 days.

How do I fix CVE-2026-31876?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2026-31876?

Run a free Strix scan to check your systems for this vulnerability.

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Source: NVD / NIST