WPForms Click5 CRM Add-on Stored XSS via Unauthenticated Endpoint

The click5 CRM add-on to WPForms WordPress plugin through 1.0.3 does not sanitise and escape content submitted through an unauthenticated endpoint before outputting it back in an admin page, leading to Stored XSS which could be used against high privilege users such as admin.

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 click5 CRM add-on for WPForms WordPress plugin versions through 1.0.3 contains a critical stored cross-site scripting (XSS) vulnerability that allows attackers to inject malicious JavaScript through an unauthenticated endpoint. The vulnerability stems from insufficient input sanitization and output escaping, meaning user-supplied content is stored in the database and later rendered on admin pages without proper filtering. This directly impacts WordPress administrators and other high-privilege users who access the affected pages, potentially leading to account compromise, malware distribution, or lateral movement within the WordPress environment. With a CVSS score of 8.8, this vulnerability poses a significant risk to any WordPress installation using the vulnerable add-on versions.

Casky's platform maps this vulnerability to MITRE ATT&CK techniques TA0001 (Initial Access) and TA0043 (Reconnaissance), identifying 323 matching security skills that detect the attack patterns at multiple stages. Practitioners using Casky would observe detections for CWE-79 violations where input validation fails at the unauthenticated endpoint—Claude's extended reasoning helps identify the data flow from submission to storage to rendering. The platform would flag suspicious script injection patterns in form submissions, anomalous database writes to admin-related tables, and HTML/JavaScript payloads in stored content that render during admin panel access. Security teams can use these skill mappings to understand both the initial compromise vector (unauthenticated input acceptance) and the exploitation mechanism (stored payload execution in privileged user context), enabling them to implement input sanitization rules, output encoding policies, and endpoint access controls to mitigate the risk.

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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-2026-84259.

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-2026-84259

Casky has 323 skills that investigate the attack patterns behind CVE-2026-84259. Run one and get CVSS-scored findings in 3 minutes.

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