CVE-2025-28931 Overview
CVE-2025-28931 is a Cross-Site Request Forgery (CSRF) vulnerability in the DevriX Hashtags (wp-hashtags) WordPress plugin that chains into a Stored Cross-Site Scripting (XSS) condition. The flaw affects all plugin versions up to and including 0.3.2. An attacker who tricks an authenticated administrator into clicking a crafted link can submit forged requests that persist malicious JavaScript into the site database. Subsequent visitors executing the stored payload allow session hijacking, administrative action abuse, and content tampering. The issue is tracked under CWE-352: Cross-Site Request Forgery.
Critical Impact
A successful exploit lets unauthenticated attackers achieve persistent script execution in administrator browser sessions through a single click on a malicious link.
Affected Products
- DevriX Hashtags (wp-hashtags) WordPress plugin versions through 0.3.2
- WordPress sites with the Hashtags plugin installed and active
- Administrator and editor accounts authenticated to vulnerable installations
Discovery Timeline
- 2025-03-11 - CVE-2025-28931 published to NVD
- 2026-04-23 - Last updated in NVD database
Technical Details for CVE-2025-28931
Vulnerability Analysis
The vulnerability combines two weaknesses in the wp-hashtags plugin. First, state-changing endpoints lack proper CSRF protection, meaning the plugin does not validate WordPress nonces (wp_verify_nonce) on form submissions. Second, user-supplied input passed through these endpoints is stored without sufficient sanitization or output encoding, producing a Stored XSS sink.
When an authenticated administrator visits an attacker-controlled page, the browser automatically attaches authentication cookies to a forged POST request directed at the plugin's settings handler. The plugin processes the request as legitimate and writes attacker-controlled markup to the database. The payload executes whenever any user renders the affected page, including privileged backend views.
Root Cause
The root cause is missing anti-CSRF token verification on plugin write actions, compounded by absent input sanitization (sanitize_text_field, wp_kses) and missing output escaping (esc_html, esc_attr). The combination converts a same-site request forgery into a persistent script injection primitive.
Attack Vector
Exploitation requires user interaction (UI:R) but no privileges on the target system. The attacker hosts a page with an auto-submitting form or image tag pointing at the vulnerable plugin endpoint. When an administrator with an active WordPress session loads that page, the browser issues the authenticated request. The injected payload then executes in the security context of the WordPress site, enabling cookie theft, CSRF chaining to other plugins, or rogue account creation. See the Patchstack Vulnerability Advisory for advisory details.
Detection Methods for CVE-2025-28931
Indicators of Compromise
- Unexpected <script>, onerror, or onload attributes appearing in hashtag-related plugin records or post metadata
- Outbound requests from administrator browser sessions to unfamiliar domains shortly after visiting external links
- New WordPress administrator accounts or modified user roles created without a corresponding audit trail entry
Detection Strategies
- Audit the WordPress database for stored hashtag entries containing HTML or JavaScript syntax using SQL pattern searches against plugin tables and wp_options
- Inspect web server access logs for POST requests to wp-hashtags endpoints lacking a Referer header matching the site origin
- Review plugin file integrity against the official distribution to identify unauthorized modifications
Monitoring Recommendations
- Enable WordPress security logging plugins to capture administrative actions, plugin setting changes, and user creation events
- Forward web server and PHP error logs to a centralized SIEM for correlation of CSRF and XSS indicators
- Alert on Content Security Policy (CSP) violation reports that flag inline script execution on administrative pages
How to Mitigate CVE-2025-28931
Immediate Actions Required
- Deactivate and remove the DevriX Hashtags plugin until a patched release is verified, since the vulnerability affects all versions through 0.3.2
- Force-rotate administrator passwords and invalidate active WordPress sessions to revoke any stolen authentication cookies
- Audit user accounts, scheduled tasks (wp_cron), and theme or plugin files for unauthorized modifications introduced via the XSS payload
Patch Information
No fixed version is identified in the available advisory data. Monitor the Patchstack Vulnerability Advisory and the DevriX vendor channels for an updated release that adds nonce verification and output escaping.
Workarounds
- Restrict access to /wp-admin/ using IP allowlisting at the web server or WAF layer to reduce the chance an administrator clicks an attacker link while authenticated
- Deploy a Web Application Firewall rule that blocks POST requests to wp-hashtags handlers without a valid same-origin Referer header
- Enforce a strict Content Security Policy that disallows inline scripts on the WordPress admin interface to limit XSS payload execution
# Example WordPress hardening: disable the vulnerable plugin via WP-CLI
wp plugin deactivate wp-hashtags
wp plugin delete wp-hashtags
# Verify removal
wp plugin list --status=active | grep -i hashtags
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
