CVE-2025-58801: 
WordPress vulnerability analysis and mitigation

CVE-2025-58801 is a Cross-Site Request Forgery (CSRF) vulnerability in the KCS Responder WordPress plugin that allows unauthenticated attackers to force higher-privileged users to execute unwanted actions. It affects all versions of the Responder plugin through 4.3.8, with version 4.4.0 serving as the patched release. The vulnerability was reported by researcher Nguyen Xuan Chien on June 18, 2025, and publicly disclosed by Patchstack on September 5, 2025. It carries a CVSS v3.1 base score of 5.4 (Medium) (Patchstack, Red Hat CVE).

The vulnerability is classified as CWE-352 (Cross-Site Request Forgery), meaning the plugin fails to properly validate that state-changing requests originate from legitimate, authenticated sessions. An unauthenticated attacker can craft a malicious web page or link that, when visited by a logged-in WordPress user with sufficient privileges, triggers unauthorized actions within the Responder plugin on their behalf. Exploitation requires user interaction — specifically, a privileged user must click a malicious link, visit a crafted page, or submit a forged form. No CSRF nonce or token validation is present to prevent such forged requests (Patchstack).

Successful exploitation allows a malicious actor to perform unauthorized actions within the Responder plugin on behalf of a higher-privileged WordPress user, such as an administrator. The CVSS assessment indicates low integrity and low availability impact with no confidentiality impact, meaning attackers could alter plugin settings or data but are unlikely to directly expose sensitive information. The practical risk is limited to the scope of actions the Responder plugin exposes to authenticated users, but in a WordPress context, administrative actions could include modifying plugin configurations or disrupting plugin functionality (Patchstack).

No public proof-of-concept exploit code or evidence of in-the-wild exploitation has been reported for CVE-2025-58801. The EPSS score is approximately 0.015% (0.000150), indicating a very low probability of exploitation in the near term. Patchstack classifies this as low priority and notes it is unlikely to be exploited, though CSRF vulnerabilities of this type are sometimes used in mass-exploit campaigns targeting WordPress plugins at scale. The vulnerability is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog (Patchstack).

1. Reconnaissance: Identify WordPress sites running the KCS Responder plugin at version 4.3.8 or earlier, using tools like WPScan or by inspecting publicly accessible plugin metadata.
2. Craft malicious payload: Create an HTML page or form that submits a forged request to the target WordPress site's Responder plugin endpoint, targeting a state-changing action (e.g., modifying plugin settings).
3. Social engineering: Deliver the malicious link or page to a privileged WordPress user (e.g., administrator) via phishing email, comment, or other communication channel.
4. Trigger exploitation: When the privileged user visits the crafted page while authenticated to the WordPress site, their browser automatically submits the forged request with their session credentials, causing the Responder plugin to execute the attacker-specified action without the user's knowledge (Patchstack).

• Logs: WordPress access logs showing unexpected POST requests to Responder plugin endpoints from unusual referrer origins or with no referrer header, particularly from IP addresses not associated with normal administrative activity.
• Application: Unexpected changes to Responder plugin settings or configurations that administrators do not recall making.
• Network: Requests to WordPress admin-ajax.php or plugin-specific endpoints originating from external or unfamiliar domains in server access logs.

The vendor has released version 4.4.0 of the KCS Responder WordPress plugin, which addresses this CSRF vulnerability. Site administrators should update the Responder plugin to version 4.4.0 or later immediately. If an immediate update is not possible, consider temporarily deactivating the plugin or restricting access to the WordPress admin area to trusted IP addresses. Patchstack users can enable auto-update for vulnerable plugins as an additional safeguard (Patchstack).