WordPress Form Builder Plugin Stored XSS via Post Meta

The JetFormBuilder — Dynamic Blocks Form Builder plugin for WordPress is vulnerable to Stored Cross-Site Scripting via 'choice' Post Meta via Insert/Update Post Action in all versions up to, and including, 3.6.5.4 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 injected payload is submitted via the unauthenticated wp_ajax_nopriv_jet_form_builder_submit endpoint, stored verbatim into post meta through the Insert/Update Post action, and later rendered unescaped by the Select Field block template when the get_from_db option generator copies raw meta values into option value attributes and label content.

Casky was already ahead

This CVE exploits attack patterns that Casky's 323matched skills already investigate — long before this vulnerability was disclosed. Claude's reasoning model maps these techniques to MITRE ATT&CK, so practitioners who ran these skills have already seen the threat behaviour in their findings.

Analysis

The JetFormBuilder plugin for WordPress contains a stored cross-site scripting (XSS) vulnerability in versions up to 3.6.5.4, allowing unauthenticated attackers to inject malicious scripts through the 'choice' post meta parameter in the Insert/Update Post Action. Because the vulnerability requires no authentication and persists in the database, any visitor accessing an affected page will execute the attacker's payload, making this a high-severity threat (CVSS 7.2) to all WordPress sites using this popular form-building plugin. This vulnerability directly impacts website integrity, user data theft, and credential harvesting at scale across potentially thousands of installations.

Casky's 323 mapped security skills leverage Claude AI's extended reasoning to detect the attack patterns behind this vulnerability across MITRE ATT&CK techniques TA0001 (Initial Access) and TA0043 (Reconnaissance). Practitioners using Casky will identify suspicious patterns including: unauthenticated AJAX requests to wp_ajax_nopri endpoints with script-like payloads in post meta fields, DOM-based indicators of script injection in page responses, and metadata attributes containing unescaped HTML/JavaScript. The platform's skill mapping will flag insufficient input sanitization in form field processing and missing output encoding in post meta rendering as the root causes. Security teams will see findings correlating unauthenticated form submissions with persistent page modifications, enabling rapid detection of exploitation attempts and already-compromised forms before widespread user exposure occurs.

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Casky Risk Score

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EPSS Probability

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Shodan Exposure

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GreyNoise Signal

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Composite risk scoring from EPSS, CISA KEV, Shodan, and GreyNoise — 21 security APIs correlated into a single Casky Risk Score. Coming in Casky Pro. Join early access →

323 Casky skills cover this attack pattern

These skills use Claude AI's reasoning model to surface findings in the same attack categories as CVE-2026-97342.

Abuse of Public-Facing API: Mobile API Abuse

mobile security · low

Run

abusing-dpapi-for-credential-access

red teaming · high

Run

abusing-shadow-credentials-for-privesc

red teaming · high

Run

MITRE ATT&CK Techniques

TA0001 TA0043

Investigate the attack patterns behind CVE-2026-97342

Casky has 323 skills that investigate the attack patterns behind CVE-2026-97342. Run one and get CVSS-scored findings in 3 minutes.

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