The Companion Auto Update plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the ‘update_delay_days’ parameter in all versions up to, and including, 3.9.2 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with administrator-level access, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This only affects multi-site installations and installations where unfiltered_html has been disabled.
Conclusion & alert: CVE-2025-4369 is rated Low Risk (27.2/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.24%). 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 | 2026-06-15 | 0.29% | 0.24% | -0.05% |
| 2 | 2026-05-11 | 0.07% | 0.29% | +0.22% |
| 3 | 2026-03-31 | — | 0.07% | — |
Full EPSS history (6 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 5.5 | 3.1 | MEDIUM |
|
2.3 | 2.7 | [email protected] |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| No affected products in dataset. | |||