CVE-2025-31440 Overview
CVE-2025-31440 is a Cross-Site Request Forgery (CSRF) vulnerability in the Strategy11 Team Terms of Use WordPress plugin (terms-of-use-2). The flaw chains into a Stored Cross-Site Scripting (XSS) condition, enabling attackers to persist malicious JavaScript through forged administrative requests. The vulnerability affects all plugin versions up to and including 2.0. The weakness is tracked under CWE-352: Cross-Site Request Forgery. Exploitation requires an authenticated administrator to visit an attacker-controlled page while logged into the target WordPress site.
Critical Impact
A successful attack stores attacker-controlled JavaScript in plugin-managed content, executing in the browser of every visitor or administrator who loads the affected page.
Affected Products
- Strategy11 Team Terms of Use plugin (terms-of-use-2) for WordPress
- All versions from n/a through 2.0
- WordPress sites with the plugin actively installed
Discovery Timeline
- 2025-03-28 - CVE-2025-31440 published to the National Vulnerability Database (NVD)
- 2026-04-23 - Last updated in NVD database
Technical Details for CVE-2025-31440
Vulnerability Analysis
The vulnerability combines two web application weaknesses into a single attack chain. The plugin lacks anti-CSRF token validation on state-changing requests that update plugin content. It also fails to sanitize or encode user-supplied input before storing it and rendering it back to browsers.
An attacker hosts a malicious page containing a forged form or fetch request targeting the plugin's administrative endpoint. When a logged-in administrator visits the page, the browser submits the request with valid session cookies. The plugin processes the request and stores the attacker's payload, including arbitrary HTML or JavaScript.
The stored payload executes in any subsequent context that renders the affected field. This produces session hijacking, administrative account takeover, malicious redirects, or further plugin and theme tampering.
Root Cause
The root cause is the absence of WordPress nonce verification (wp_verify_nonce) on privileged update handlers combined with missing output escaping (esc_html, esc_attr, or wp_kses) on the stored field. Either control would break the exploit chain; both are missing.
Attack Vector
The attack is delivered over the network and requires user interaction. The attacker must convince an authenticated administrator to load a malicious URL while their WordPress session is active. The scope change reflected in the CVSS vector indicates that the injected script executes against users outside the originally authenticated context. See the Patchstack Vulnerability Advisory for additional technical context.
Detection Methods for CVE-2025-31440
Indicators of Compromise
- Unexpected <script>, onerror, onload, or javascript: strings stored in Terms of Use plugin records within the WordPress database
- Outbound requests from administrator browsers to unfamiliar domains shortly after viewing plugin-managed pages
- New or modified WordPress administrator accounts created without a corresponding audit log entry
- HTTP referer values pointing to external attacker-controlled domains in WordPress access logs preceding plugin updates
Detection Strategies
- Inspect wp_options, wp_posts, and any plugin-specific tables for HTML or JavaScript content in fields expected to contain plain text
- Review web server logs for POST requests to plugin endpoints lacking valid _wpnonce parameters
- Correlate administrator session activity with referrers originating outside the WordPress admin domain
- Apply content security policy (CSP) violation reporting to surface script execution from unexpected inline sources
Monitoring Recommendations
- Enable WordPress audit logging plugins to capture all administrator-initiated content changes
- Monitor file integrity for the terms-of-use-2 plugin directory to identify unauthorized modifications
- Alert on any creation of administrative users or modifications to existing privileged accounts
- Track outbound DNS queries from administrator workstations during active WordPress sessions
How to Mitigate CVE-2025-31440
Immediate Actions Required
- Deactivate the Strategy11 Team Terms of Use plugin (terms-of-use-2) until a patched version is confirmed available
- Audit plugin-managed content for previously injected HTML or JavaScript and remove malicious payloads
- Force password resets and session invalidation for all WordPress administrator accounts
- Review WordPress user tables for unauthorized accounts created during the exposure window
Patch Information
At the time of publication, the Patchstack advisory lists all versions through 2.0 as affected. Administrators should monitor the plugin's repository page for an updated release and apply it immediately when published. If no fixed version exists, removal of the plugin is the only definitive remediation.
Workarounds
- Restrict WordPress administrator access to dedicated browsers or browser profiles that do not visit untrusted sites
- Deploy a web application firewall (WAF) rule to block POST requests to plugin endpoints lacking valid WordPress nonces
- Enforce a strict Content Security Policy that disallows inline scripts on WordPress admin and front-end pages
- Limit administrative accounts to the minimum required and require multi-factor authentication on all of them
# Configuration example: disable the vulnerable plugin via WP-CLI
wp plugin deactivate terms-of-use-2
wp plugin delete terms-of-use-2
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
