CVE-2025-10691 identifies a Cross-Site Request Forgery (CSRF) vulnerability in the yudiz Easy Email Subscription plugin for WordPress, affecting all versions up to and including 1.3. The vulnerability stems from missing or incorrect nonce validation in the show_editsub_page() function, which is responsible for managing subscriber edits. Nonces in WordPress are security tokens used to verify that requests originate from legitimate users and not from malicious third parties. The absence of proper nonce checks means that an attacker can craft a malicious request that, when executed by an authenticated site administrator (e.g., by clicking a link), causes the deletion of arbitrary subscribers without the administrator’s explicit consent. This attack does not require the attacker to be authenticated but does require user interaction from a privileged user, making it a classic CSRF scenario. The impact is primarily on the integrity of subscriber data, as attackers can delete subscribers, potentially disrupting marketing or communication efforts. Confidentiality and availability are not directly affected. The vulnerability has a CVSS 3.1 base score of 4.3, indicating medium severity, with an attack vector of network, low complexity, no privileges required, user interaction required, and unchanged scope. No public exploits or patches are currently available, so organizations must rely on mitigating controls until an official fix is released.

For European organizations, this vulnerability can lead to unauthorized deletion of email subscribers, undermining marketing campaigns, customer engagement, and communication channels. Organizations relying heavily on email subscription lists for business operations, especially in sectors like e-commerce, media, and digital marketing, may experience data integrity issues and loss of subscriber trust. Although the vulnerability does not expose sensitive subscriber information or cause service outages, the manipulation of subscriber data can disrupt business workflows and lead to reputational damage. Since exploitation requires tricking an administrator into clicking a malicious link, organizations with less mature security awareness programs are at higher risk. The impact is more pronounced for organizations with large subscriber bases and those that use the affected plugin extensively on public-facing WordPress sites.

1. Implement proper nonce validation in the show_editsub_page() function to ensure all requests modifying subscriber data are verified as legitimate. 2. Restrict access to subscription management pages and functions to only trusted administrators and enforce least privilege principles. 3. Educate site administrators and privileged users about the risks of phishing and social engineering attacks, emphasizing caution when clicking links from untrusted sources. 4. Monitor WordPress plugin updates from yudiz and apply patches promptly once available. 5. Employ web application firewalls (WAFs) with rules to detect and block suspicious CSRF attempts targeting subscription management endpoints. 6. Consider temporarily disabling or replacing the Easy Email Subscription plugin if immediate patching is not possible, especially in high-risk environments. 7. Conduct regular security audits and penetration testing focused on WordPress plugins and administrative interfaces to identify and remediate similar vulnerabilities.