CVE-2025-66548

low-risk
Published 2025-12-05

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.

Do I need to act?

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0.02% chance of exploitation
EPSS score — low exploit probability
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Not on CISA KEV list
No confirmed active exploitation reported to CISA
?
Patch status unknown
Check vendor advisories for fix availability and mitigation guidance
3
CVSS 3.3/10 Low
LOCAL / LOW complexity

Affected Products (1)

Deck

Affected Vendors

Nextcloud

References (4)

Patch https://github.com/nextcloud/deck/commit/afa95d3c507465b9d31af7c88c69b76711ef185...
Issue Tracking https://github.com/nextcloud/deck/pull/6671
Patch https://github.com/nextcloud/security-advisories/security/advisories/GHSA-xjvq-x...
Permissions Required https://hackerone.com/reports/2326618
18
/ 100
low-risk
Severity 13/34 · Low
Exploitability 0/34 · Minimal
Exposure 5/34 · Minimal