Cool FormKit Lite <= 2.7.9 - Authenticated (Contributor+) Stored DOM-Based Cross-Site Scripting via Form Field custom_id Parameter
Strategic Overview
- Status
- Patched in 2.7.10
- Affected Plugin
- Cool FormKit Lite – Advanced Form Builder for Elementor
- Affected Version
<= 2.7.9- CVSS
- 6.4Medium
- Weakness type
- CWE-79 · Improper Neutralization of Input During Web Page Generation
- CVE
CVE-2026-118500
At a glance
CVE-2026-118500 is a medium-severity Improper Neutralization of Input During Web Page Generation vulnerability in the Cool FormKit Lite WordPress plugin, affecting versions <= 2.7.9. It carries a CVSS score of 6.4 (reachable over the network; low attack complexity). Exploitation requires an authenticated account at Contributor level or above. The issue is fixed in version 2.7.10; sites on affected versions should update now. Disclosed October 2026, reported by Wordfence PRISM.
Vulnerability Overview
The Cool FormKit Lite – Advanced Form Builder for Elementor plugin for WordPress is vulnerable to Stored DOM-Based Cross-Site Scripting via the '_elementor_data.form_fields[].custom_id' parameter in all versions up to, and including, 2.7.9 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. The esc_html() call applied at server emission is bypassed because the HTML fragment-serialization algorithm restores " to a raw double-quote inside text nodes when jQuery .html() extracts the template, allowing the attacker-controlled custom_id to break out of an HTML attribute context within the plugin's own frontend script.
Technical Analysis
The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed, and no interaction from a victim user.
CWE-79: Improper Neutralization of Input During Web Page Generation
Cool FormKit Lite <= 2.7.9 carries this weakness at esc_html(), and reaching it takes an account at Contributor level or above. Cross-site scripting happens when input from a request is written into a page without being escaped for the context it lands in, so the browser parses attacker-supplied text as markup or script.
Injected script runs with the privileges of whoever views the affected page, which is how these flaws turn into administrator session theft, silent account creation or persistent backdoors in page content. For Cool FormKit Lite the fix is 2.7.10: builds <= 2.7.9 are affected, anything from 2.7.10 onward is not.
Remediation
Update to version 2.7.10, or a newer patched version
How does WordSec protect against this?
An attacker needs Contributor access first, so the firewall sees the attempt as traffic from a logged-in account: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: Cool FormKit Lite 2.7.10 closes this, and updating the plugin is the step that ends it.
- Firewall
- Alerts
External References
Related records
Same weakness class
Vulnerability data © Defiant, Inc., provided under the Wordfence Intelligence T&C