CVE-2025-66548

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.

Score

CVSS 3.1 5.5 Medium

Status

Analyzed - security-advisories@github.com

Published

2025-12-05

Last modified

2026-10-15

Weaknesses

CWE-116

Affected products

• Deck (Nextcloud)
• Security-advisories (Nextcloud)

References

• https://github.com/nextcloud/security-advisories/security/advisories/GHSA-xjvq-xvr7-xpg6
• https://github.com/nextcloud/deck/pull/6671
• https://github.com/nextcloud/deck/commit/afa95d3c507465b9d31af7c88c69b76711ef185a
• https://hackerone.com/reports/2326618