CVE-2025-66548

Nextcloud Deck app allows to spoof file extensions by using RTLO characters

State: Published
Severity: 3.3 Low
Published: Dec 5, 2025
Updated: Dec 8, 2025
Reserved: Dec 4, 2025

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.

Scores

CVSS	Score	Vector	Source
3.1	3.3 Low	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N	GitHub_M

Weaknesses

CWE-116 Improper Encoding or Escaping of Output

Affected Products

Product	Versions
security-advisoriesnextcloud	>= 1.15.0-beta.1, < 1.15.1Affected >= 1.14.0-beta.1, < 1.14.4Affected < 1.12.7Affected

References

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