Nextcloud Server is a self hosted personal cloud system. In Nextcloud Server and Enterprise Server prior to 30.0.9 and 31.0.1, incorrect path handling with groupfolders caused the admin_audit app to not properly log all actions on files and folders inside groupfolders. This vulnerability is fixed in Nextcloud Server and Enterprise Server prior to 30.0.9 and 31.0.1.
Conclusion & alert: CVE-2025-66552 is rated Low Risk (20.6/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.03%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-03-04 | 0.06% | 0.03% | -0.02% |
| 2 | 2026-03-01 | 0.03% | 0.06% | +0.02% |
| 3 | 2025-12-10 | — | 0.03% | — |
Full EPSS history (4 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 4.3 | 3.1 | MEDIUM |
|
2.8 | 1.4 | [email protected] |
| 4.3 | 3.1 | MEDIUM |
|
2.8 | 1.4 | [email protected] |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| nextcloud | nextcloud_server | >= 30.0.0, < 30.0.9 | cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:-:*:*:* |
| nextcloud | nextcloud_server | >= 30.0.0, < 30.0.9 | cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:enterprise:*:*:* |
| nextcloud | nextcloud_server | >= 31.0.0, < 31.0.1 | cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:-:*:*:* |
| nextcloud | nextcloud_server | >= 31.0.0, < 31.0.1 | cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:enterprise:*:*:* |
| URL | Tags |
|---|---|
| https://github.com/nextcloud/security-advisories/security/advisories/GHSA-ww9m-f8j4-jj9x | Patch Vendor Advisory |
| https://github.com/nextcloud/server/commit/7cc005c43c72bc384848cf8cb851895827c412f6 | Patch |
| https://github.com/nextcloud/server/pull/50992 | Issue Tracking |
| https://hackerone.com/reports/2890071 | Issue Tracking Vendor Advisory |