CVE-2025-14904: 
WordPress vulnerability analysis and mitigation

CVE-2025-14904 is a Cross-Site Request Forgery (CSRF) vulnerability in the Newsletter Email Subscribe plugin for WordPress, affecting versions up to and including 2.4. The flaw stems from incorrect nonce validation in the nels_settings_page function, allowing unauthenticated attackers to modify plugin settings by tricking a site administrator into clicking a malicious link. It was published on January 7, 2026, with Wordfence as the reporting CNA. The vulnerability carries a CVSS v3.1 base score of 4.3 (Medium) (Wordfence).

The root cause is improper nonce validation (CWE-352) in the nels_settings_page function of the Newsletter Email Subscribe plugin. WordPress nonces are used to verify the authenticity of requests; when validation is incorrect or absent, an attacker can craft a forged HTTP request that the server accepts as legitimate. Exploitation requires social engineering — the attacker must lure an authenticated administrator into triggering the forged request (e.g., by clicking a crafted link or visiting a malicious page), at which point the plugin's settings are updated without the administrator's knowledge. The vulnerable code path is visible in the plugin source at line 109 of newsletter-email-subscribe.php version 2.4 (Plugin Source, Wordfence).

Successful exploitation allows an unauthenticated attacker to modify the Newsletter Email Subscribe plugin's settings on the affected WordPress site, impacting integrity. There is no direct confidentiality or availability impact, as the attacker cannot read data or disrupt service through this vector alone. However, manipulated plugin settings could be leveraged to redirect newsletter subscriptions, inject malicious content into email campaigns, or alter subscriber management behavior, potentially affecting site users and reputation (Wordfence).

No public proof-of-concept exploit code or evidence of in-the-wild exploitation has been reported for CVE-2025-14904. The EPSS score is approximately 0.013% (0.000130), indicating a very low probability of exploitation in the near term. The vulnerability is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog. Exploitation requires user interaction from a privileged user (site administrator), which limits opportunistic mass exploitation (Wordfence).

1. Reconnaissance: Identify WordPress sites running the Newsletter Email Subscribe plugin version 2.4 or earlier, using tools like WPScan or by inspecting publicly accessible plugin metadata.
2. Craft malicious request: Construct a forged HTTP POST request targeting the nels_settings_page function with desired plugin settings (e.g., altered email addresses or notification settings), exploiting the missing/incorrect nonce check.
3. Deliver payload: Embed the forged request in a malicious webpage, image tag, or link (e.g., via a phishing email or a comment on a forum) designed to be triggered when an authenticated administrator visits or clicks it.
4. Trigger CSRF: When the administrator's browser loads the attacker-controlled content while authenticated to the WordPress admin panel, the forged request is automatically submitted with the administrator's session cookies.
5. Settings modified: The plugin processes the request as legitimate, updating its settings to values controlled by the attacker without any indication to the administrator (Wordfence).

• Logs: WordPress admin audit logs or server access logs showing unexpected POST requests to the plugin's settings page (/wp-admin/admin.php?page=nels_settings_page or similar) from unusual referrers or at unusual times.
• File System: Unexpected changes to plugin configuration stored in the WordPress database (wp_options table entries related to the Newsletter Email Subscribe plugin) that do not correspond to administrator activity.
• Network: HTTP POST requests to the WordPress admin settings endpoint originating from external or unexpected referrer URLs, particularly if the Referer header points to an unknown external domain.

WordPress site administrators should update the Newsletter Email Subscribe plugin to version 2.5 or later, which addresses the improper nonce validation. Until an update can be applied, administrators should exercise caution when clicking links in emails or visiting untrusted websites while logged into the WordPress admin panel. Disabling the plugin temporarily is also a viable workaround if the update cannot be applied immediately (Wordfence).