The MasterStudy LMS Pro plugin for WordPress is vulnerable to arbitrary file uploads due to a missing file type validation in the stm_lms_add_assignment_attachment function in all versions up to, and including, 4.7.0. This makes it possible for authenticated attackers, with Subscriber-level access and above, to upload arbitrary files on the affected site's server, which may make remote code execution possible.
Conclusion & alert: CVE-2025-4800 is rated Moderate Risk (64.7/100): CVSS High severity, with medium exploitation likelihood (EPSS 1.59%). Mandatory action: Review affected assets and schedule remediation.
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 | 2026-03-24 | 0.60% | 1.59% | +1.00% |
| 2 | 2026-02-11 | 0.49% | 0.60% | +0.11% |
| 3 | 2026-01-31 | — | 0.49% | — |
Full EPSS history (11 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 8.8 | 3.1 | HIGH |
|
2.8 | 5.9 | [email protected] |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| No affected products in dataset. | |||