Vulnerability in Nextcloud Deck
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 3.3 (Low). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N.
EPSS exploit prediction
EPSS: 0.002 (3.8th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 4th percentile — 3.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: +0.000
Affected products
- Nextcloud Deck
- Nextcloud Security-Advisories — versions >= 1.15.0-beta.1, < 1.15.1, >= 1.14.0-beta.1, < 1.14.4, < 1.12.7
Weakness classification (CWE)
References
- github.com/nextcloud/security-advisories/security/advisories/GHSA-xjvq-xvr7-xpg6 (Patch, Vendor Advisory)
- github.com/nextcloud/deck/pull/6671 (Issue Tracking)
- github.com/nextcloud/deck/commit/afa95d3c507465b9d31af7c88c69b76711ef185a (Patch)
- hackerone.com/reports/2326618 (Permissions Required, Vendor Advisory)
Frequently asked questions
- What is CVE-2025-66548?
- CVE-2025-66548 is a low-severity vulnerability in Nextcloud Deck, classified under Improper Encoding or Escaping of Output. CVSS score: 3.3/10. Published 2025-12-05.
- How severe is CVE-2025-66548?
- Low severity. CVSS v3 base score is 3.3 out of 10.