CVE-2025-27355 identifies a Cross-Site Request Forgery (CSRF) vulnerability in the Nicolas GRILLET Woocommerce – Loi Hamon plugin, affecting versions up to and including 1.1.0. This plugin integrates French consumer protection law (Loi Hamon) compliance features into Woocommerce-based e-commerce sites. The vulnerability allows attackers to craft malicious requests that, when executed by an authenticated user (such as an administrator or store manager), can perform unauthorized actions without their consent. The CSRF flaw is compounded by the presence of stored Cross-Site Scripting (XSS), meaning that malicious scripts can be injected and persist within the application, affecting all users who view the compromised content. This combination significantly increases the attack surface, enabling attackers to steal session tokens, manipulate site content, or escalate privileges. Exploitation requires the victim to be authenticated and visit a maliciously crafted webpage, but no additional user interaction is necessary. No official patch or CVSS score has been published yet, and no known exploits have been reported in the wild. The vulnerability highlights the importance of proper CSRF token implementation and rigorous input validation in WordPress plugins, especially those handling legal or transactional data.

The impact of CVE-2025-27355 is considerable for organizations using the affected Woocommerce – Loi Hamon plugin. Successful exploitation can lead to unauthorized actions performed with the privileges of authenticated users, including administrators, potentially resulting in site defacement, data manipulation, or injection of malicious scripts that affect all visitors (stored XSS). This can compromise confidentiality by stealing sensitive user data or session cookies, integrity by altering site content or orders, and availability if malicious scripts disrupt normal operations. E-commerce platforms are particularly sensitive to such attacks due to their role in handling financial transactions and customer information. The stored XSS aspect increases the risk of widespread compromise, as injected scripts persist and affect multiple users. Although no exploits are currently known in the wild, the vulnerability presents a high risk if weaponized, especially given the plugin’s role in legal compliance, which may attract targeted attacks. Organizations could face reputational damage, regulatory penalties, and financial loss if exploited.

To mitigate CVE-2025-27355, organizations should immediately monitor for updates or patches from the plugin vendor and apply them as soon as they become available. Until a patch is released, administrators should consider disabling the Woocommerce – Loi Hamon plugin if feasible or restricting its use to trusted users only. Implementing Web Application Firewall (WAF) rules to detect and block CSRF attack patterns and suspicious POST requests can provide temporary protection. Additionally, site owners should enforce strict Content Security Policy (CSP) headers to limit the impact of stored XSS. Regularly auditing and sanitizing all user inputs and stored content within the plugin’s scope can reduce the risk of script injection. Enforcing multi-factor authentication (MFA) for administrative accounts can limit the damage if credentials are compromised. Finally, educating users about the risks of visiting untrusted websites while logged into the e-commerce backend can help reduce CSRF exploitation likelihood.