CVE-2023-39955

Name: CVE-2023-39955
Creator: NVD / NIST
Published: 2023-08-10T15:15:09.807+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 6.1/10EPSS 0.48%

Last modified Jun 17, 2026

CVE-2023-39955 is a medium-severity vulnerability rated 6.1/10 on the CVSS scale. Notes is a note-taking app for Nextcloud, an open-source cloud platform. Starting in version 4.4.0 and prior to version 4.8.0, when creating a note file with HTML, the content is rendered in the preview instead of the file being offered to download. EPSS estimates a 0.48% chance of exploitation in the next 30 days.

Description

Notes is a note-taking app for Nextcloud, an open-source cloud platform. Starting in version 4.4.0 and prior to version 4.8.0, when creating a note file with HTML, the content is rendered in the preview instead of the file being offered to download. Nextcloud Notes app version 4.8.0 contains a patch for the issue. No known workarounds are available.

Metrics

CVSS 3.1

6.1/10

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

EPSS Probability

0.48%

37.8th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-79

Affected Software

Vendor	Product	Versions
Nextcloud	Notes	>= 4.4.0, < 4.8.0

References

https://github.com/nextcloud/notes/pull/1031Patch
https://github.com/nextcloud/security-advisories/security/advisories/GHSA-6g88-37x7-4vw6Patch, Vendor Advisory
https://hackerone.com/reports/1924355Third Party Advisory
https://github.com/nextcloud/notes/pull/1031Patch
https://github.com/nextcloud/security-advisories/security/advisories/GHSA-6g88-37x7-4vw6Patch, Vendor Advisory
https://hackerone.com/reports/1924355Third Party Advisory

Timeline

Published: Aug 10, 2023
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2023-39955?

How severe is CVE-2023-39955?

CVE-2023-39955 has a CVSS score of 6.1/10 (MEDIUM severity). The EPSS model estimates a 0.48% probability of exploitation in the next 30 days.

How do I fix CVE-2023-39955?

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-2023-39955?

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

Scan your code now

Source: NVD / NIST