Information disclosure in Nextcloud Desktop
CVE-2025-66549
Nextcloud Desktop is the desktop sync client for Nextcloud. Prior to 3.16.5, when trying to manually lock a file inside an end-to-end encrypted directory, the path of the file was sent to the server unencrypted, making it possible for administrators to see it in log files. This vulnerability is fixed in 3.16.5.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 2.4 (Low). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:L/I:N/A:N.
EPSS exploit prediction
EPSS: 0.003 (20.1th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 20th percentile — 20.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: +0.000
Affected products
- Nextcloud Desktop
- Nextcloud Security-Advisories — versions < 3.16.5
Weakness classification (CWE)
References
- github.com/nextcloud/security-advisories/security/advisories/GHSA-h9xj-qh76-q3hw (Patch, Vendor Advisory)
- github.com/nextcloud/desktop/pull/8330 (Issue Tracking)
- github.com/nextcloud/desktop/commit/36d6c234d42b06a6f2e9de3e413a5c3c625edad6 (Patch)
- hackerone.com/reports/3159877 (Permissions Required, Vendor Advisory)
Frequently asked questions
- What is CVE-2025-66549?
- CVE-2025-66549 is a low-severity vulnerability in Nextcloud Desktop, classified under Generation of Error Message Containing Sensitive Information. CVSS score: 2.4/10. Published 2025-12-05.
- How severe is CVE-2025-66549?
- Low severity. CVSS v3 base score is 2.4 out of 10.