CVE-2025-66548 LOW

CVE-2025-66548: Nextcloud Deck app allows to spoof file extensions by using RTLO characters

Vendor Nextcloud
Product security-advisories
Weakness CWE-116
Published December 5, 2025
Last update December 8, 2025
View on NVD All CVEs

CVSS base score

3.3/10
Attack vector Local
Attack complexity Low
Privileges required Low
User interaction None
Confidentiality None
Integrity Low

CVSS vector

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

What the vulnerability does

01Description

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.

Key dates

02Disclosure timeline

December 5, 2025 CVE published
December 8, 2025 Record updated