CVE-2025-14795 identifies a Cross-Site Request Forgery (CSRF) vulnerability in the Stop Spammers Classic plugin for WordPress, a widely used anti-spam tool. The vulnerability exists in all versions up to and including 2026.1 due to missing nonce validation in the ss_addtoallowlist class. Nonce tokens are security measures designed to ensure that requests to perform sensitive actions originate from legitimate users and not from malicious third-party sites. The absence of nonce validation means that an attacker can craft a malicious web request that, when executed by an authenticated site administrator (e.g., by clicking a link), causes the plugin to add arbitrary email addresses to the spam allowlist. This effectively allows attackers to whitelist spam or malicious email addresses, thereby bypassing spam filtering mechanisms. The vulnerability does not impact confidentiality or availability but affects the integrity of the spam filtering process. The CVSS v3.1 score of 4.3 reflects a medium severity, with attack vector being network, no privileges required, low attack complexity, and requiring user interaction. The vulnerability was partially addressed in version 2026.1, but earlier versions remain fully vulnerable. No public exploits have been reported to date. This vulnerability is particularly relevant for WordPress sites that rely on Stop Spammers Classic for spam mitigation, as it can degrade the effectiveness of spam defenses and potentially increase exposure to phishing or spam campaigns.

For European organizations, the primary impact of this vulnerability lies in the potential degradation of email spam filtering integrity on WordPress sites using the Stop Spammers Classic plugin. By allowing attackers to add arbitrary email addresses to the spam allowlist, malicious actors could facilitate the delivery of phishing emails, malware-laden messages, or other unwanted communications that would otherwise be blocked. This can increase the risk of successful phishing attacks, social engineering, and malware infections, which may lead to data breaches or operational disruptions. While the vulnerability does not directly compromise confidentiality or availability, the indirect effects on organizational security posture can be significant, especially for entities relying heavily on WordPress-based web infrastructure for communications or customer interactions. Additionally, the requirement for administrator interaction means that social engineering tactics could be employed to exploit this vulnerability. Organizations in sectors with high regulatory scrutiny, such as finance, healthcare, and government, may face compliance risks if spam or phishing attacks succeed due to this weakness.

European organizations should take the following specific mitigation steps: 1) Immediately update the Stop Spammers Classic plugin to version 2026.1 or later, where partial patches have been applied; monitor vendor communications for further updates or complete fixes. 2) Implement additional CSRF protections at the WordPress site level, such as enforcing nonce validation for all sensitive actions and using security plugins that provide enhanced request validation. 3) Educate site administrators about the risks of clicking on unsolicited or suspicious links, especially those that could trigger administrative actions. 4) Employ web application firewalls (WAFs) with rules designed to detect and block CSRF attack patterns targeting WordPress plugins. 5) Regularly audit the spam allowlist to detect unauthorized entries and remove suspicious email addresses. 6) Consider restricting administrative access to trusted networks or VPNs to reduce exposure to external CSRF attempts. 7) Monitor logs for unusual administrative actions that could indicate exploitation attempts. These steps go beyond generic advice by focusing on plugin-specific updates, administrative user behavior, and layered defenses.