CVE-2026-39594: Broken Access Control in Ultra Addons for WPForms ≤1.0.11

Technical summary

CVE-2026-39594 represents an authorization bypass (CWE-862) in Ultra Addons for WPForms. The vulnerability allows authenticated subscribers or lower-privileged users to execute actions beyond their assigned capabilities. With network-accessible WordPress installations, an attacker with valid credentials—whether obtained through credential reuse, phishing, or account compromise—can exploit this flaw without user interaction. The attack vector is straightforward and the security barrier remains low, resulting in a CVSS v3.1 score of 6.4 (Medium).

Business impact

Compromised data integrity is the primary business concern. An attacker with subscriber-level access could modify form configurations, collect sensitive user submissions, or disrupt form functionality for legitimate users. While confidentiality is not directly compromised, the ability to alter or delete form data and configurations could damage customer trust, trigger compliance investigations if customer data is involved, and necessitate incident response and system restoration efforts.

Affected systems

This vulnerability impacts WordPress installations using Ultra Addons for WPForms plugin version 1.0.11 and earlier. The scope extends to the broader WordPress site because the flaw allows privilege escalation within the WPForms ecosystem. Any site where subscriber accounts exist—whether for customers, team members, or external contributors—is at risk if the plugin remains unpatched.

Exploitability

Exploitation requires valid WordPress credentials, which limits the attack surface compared to unauthenticated flaws but remains practical in real-world scenarios. The ease of exploitation is high once access is obtained; no complex manipulation or timing attacks are needed. The vulnerability is not currently listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, suggesting active exploitation in the wild has not yet been documented at scale—though absence from KEV is not a guarantee of safety.

Remediation

Update Ultra Addons for WPForms to a patched version released after 1.0.11. Verify the available update through the WordPress plugin dashboard or the official plugin repository. In parallel, audit existing subscriber and contributor accounts to identify any unusual activity or unauthorized modifications to WPForms configurations or submissions. Consider temporarily restricting lower-privilege user access to WPForms until the plugin is patched.

Patch guidance

Navigate to Plugins > Installed Plugins in your WordPress dashboard and check for an available update to Ultra Addons for WPForms. Install the update immediately once a version newer than 1.0.11 becomes available. Before updating, back up your WordPress database and configuration files. Test the update on a staging environment if possible to ensure no form functionality is disrupted. After patching, verify that all forms function as expected and that user permissions are correctly enforced.

Detection guidance

Review WordPress access logs and WPForms audit trails (if available) for unauthorized modifications to form configurations or excessive data access by subscriber-level accounts between the vulnerability publication date (June 15, 2026) and your patching date. Monitor for repeated failed form submissions or unusual query patterns that might indicate privilege escalation attempts. Enable and review WordPress security logging plugins to detect lateral movement or unauthorized capability usage by low-privilege accounts.

Why prioritize this

Despite a medium CVSS score, this vulnerability warrants prioritization because it directly enables privilege escalation within a data collection system. WPForms often handles sensitive user information, and the ability for an attacker to modify form behavior or access submissions creates both integrity and confidentiality risk. The low barrier to exploitation once credentials are obtained and the cross-site scope increase the practical risk. Organizations with subscriber-heavy WordPress communities or customer form integrations should treat this as high priority within their medium-severity backlog.

Risk score, explained

The CVSS 3.1 score of 6.4 reflects a network-accessible vulnerability requiring low privilege and low complexity but limited by the authentication requirement. The vector CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:L/A:L captures integrity and availability impacts without confidentiality loss. The scope change (S:C) indicates the vulnerability can affect resources beyond the vulnerable component—other users' forms and data. The medium rating appropriately balances the serious nature of privilege escalation against the practical limitation of requiring valid credentials.

Frequently asked questions