CVE-2025-66548

Name: CVE-2025-66548
Creator: NVD / NIST
Published: 2025-12-05T18:15:57.967+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 5.5/10EPSS 0.13%

Last modified Jun 17, 2026

CVE-2025-66548 is a medium-severity vulnerability rated 5.5/10 on the CVSS scale. Nextcloud Deck is a kanban style organization tool aimed at personal planning and project organization for teams integrated with Nextcloud. Prior to 1.12.7, 1.14.4, and 1.15.1, file extension can be spoofed by using RTLO characters, tricking users into download files with a different extension than what is displayed. EPSS estimates a 0.13% chance of exploitation in the next 30 days.

Description

Nextcloud Deck is a kanban style organization tool aimed at personal planning and project organization for teams integrated with Nextcloud. Prior to 1.12.7, 1.14.4, and 1.15.1, file extension can be spoofed by using RTLO characters, tricking users into download files with a different extension than what is displayed. This vulnerability is fixed in 1.12.7, 1.14.4, and 1.15.1.

Metrics

CVSS 3.1

5.5/10

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

EPSS Probability

0.13%

2.6th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-116

Affected Software

Vendor	Product	Versions
Nextcloud	Deck	< 1.12.7
Nextcloud	Deck	>= 1.14.0, < 1.14.4
Nextcloud	Deck	>= 1.15.0, < 1.15.1

References

https://github.com/nextcloud/deck/commit/afa95d3c507465b9d31af7c88c69b76711ef185aPatch
https://github.com/nextcloud/deck/pull/6671Issue Tracking
https://github.com/nextcloud/security-advisories/security/advisories/GHSA-xjvq-xvr7-xpg6Patch, Vendor Advisory
https://hackerone.com/reports/2326618Permissions Required, Vendor Advisory

Timeline

Published: Dec 5, 2025
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2025-66548?

How severe is CVE-2025-66548?

CVE-2025-66548 has a CVSS score of 5.5/10 (MEDIUM severity). The EPSS model estimates a 0.13% probability of exploitation in the next 30 days.

How do I fix CVE-2025-66548?

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-2025-66548?

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

Scan your code now

Source: NVD / NIST