The EG-Series plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the plugin's [series] shortcode in all versions up to, and including, 2.1.1 due to insufficient input sanitization and output escaping on user supplied attributes in the shortcode_title function. This makes it possible for authenticated attackers - with contributor-level access and above, on sites with the Classic Editor plugin activated - to inject arbitrary JavaScript code in the titletag attribute that will execute whenever a user access an injected page.
Conclusion & alert: CVE-2025-4126 is rated Low Risk (39.4/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.18%). 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 | 2026-03-11 | 0.05% | 0.18% | +0.12% |
| 2 | 2026-02-08 | 0.03% | 0.05% | +0.02% |
| 3 | 2025-11-21 | — | 0.03% | — |
Full EPSS history (7 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 6.4 | 3.1 | MEDIUM |
|
3.1 | 2.7 | [email protected] |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| No affected products in dataset. | |||