The Nextcloud Approval app allows approval or disapproval of files in the sidebar. Prior to 1.3.1 and 2.5.0, an authenticated user listed as a requester in a workflow can set another user’s file into the “pending approval” without access to the file by using the numeric file id. This vulnerability is fixed in 1.3.1 and 2.5.0.
Conclusion & alert: CVE-2025-66515 is rated Low Risk (12.8/100): CVSS Low severity, with low exploitation likelihood (EPSS 0.02%). Mandatory action: Low composite risk—no urgent action required; patch on your normal maintenance cycle and revisit priority if CVSS or EPSS increases.
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 | 2025-12-06 | — | 0.02% | — |
Full EPSS history (1 record total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 2.7 | 3.1 | LOW |
|
1.2 | 1.4 | [email protected] |
| URL | Tags |
|---|---|
| https://github.com/nextcloud/approval/commit/e30b56b7832255311ac800b7875f44866e88fff4 | Patch |
| https://github.com/nextcloud/approval/pull/334 | Issue Tracking |
| https://github.com/nextcloud/security-advisories/security/advisories/GHSA-q26g-fmjq-x5g5 | Patch Vendor Advisory |
| https://hackerone.com/reports/3338748 | Issue Tracking Vendor Advisory |