The Keep Backup Daily plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the backup title alias (`val` parameter) in the `update_kbd_bkup_alias` AJAX action in all versions up to, and including, 2.1.2. This is due to insufficient input sanitization and output escaping. While `sanitize_text_field()` strips HTML tags on save, it does not encode double quotes. The backup titles are output in HTML attribute contexts without `esc_attr()`. This makes it possible for authenticated attackers, with Administrator-level access and above, to inject arbitrary web scripts via attribute injection that will execute whenever another administrator views the backup list page.
Conclusion & alert: CVE-2026-3577 is rated Low Risk (20.9/100): 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 | 2026-03-21 | — | 0.03% | — |
Full EPSS history (1 record total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 4.4 | 3.1 | MEDIUM |
|
1.3 | 2.7 | [email protected] |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| No affected products in dataset. | |||