XSS in Wpforms Pro

CVE-2026-18409

The WPForms Pro plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Single Line Text and Paragraph Text Field Values in all versions up to, and including, 2.0.0.2 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. The exploit relies on the plugin's own wp_kses_allowed_html filter widening the 'post' allowlist to permit iframe elements with a data-src attribute, which is not on WordPress's URI-attribute sanitization list, allowing a javascript: URI stored in data-src to survive kses processing and subsequently be promoted to a live src attribute by the bundled admin script view-entry.min.js.

Vulnerability class: XSS (Cross-Site Scripting)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 7.2 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.003 (25.4th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 25th percentile — 25.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-18409: held from 0.002 to 0.003.

EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.001

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-18409?
CVE-2026-18409 is a high-severity vulnerability in Wpforms Pro, classified under Cross-site Scripting. CVSS score: 7.2/10. Published 2026-08-21.
How severe is CVE-2026-18409?
High severity. CVSS v3 base score is 7.2 out of 10.