CVE-2025-62739 identifies a Cross-Site Request Forgery (CSRF) vulnerability in the SaifuMak Add Custom Codes plugin, specifically versions up to and including 4.80. CSRF vulnerabilities occur when a web application does not adequately verify that requests modifying state originate from legitimate users, allowing attackers to craft malicious requests that an authenticated user unknowingly executes. In this case, the Add Custom Codes plugin lacks sufficient protections against CSRF attacks, enabling an attacker to induce an authenticated user to perform unauthorized actions such as adding or modifying custom code snippets. These custom codes could be JavaScript or other scripts that affect the behavior or security posture of the web application. Although no exploits have been reported in the wild, the vulnerability is publicly disclosed and could be targeted by attackers seeking to manipulate website behavior or escalate privileges indirectly. The absence of a CVSS score indicates that the vulnerability has not yet been fully assessed for severity, but the nature of CSRF vulnerabilities typically implies a significant risk when exploited in administrative or customization contexts. The vulnerability affects all versions up to 4.80, with no patch links currently available, highlighting the need for immediate attention from users of the plugin. The vulnerability was reserved in October 2025 and published in December 2025, indicating recent discovery and disclosure. The plugin is used to add custom code snippets, which are critical for site customization but can also introduce security risks if manipulated maliciously. Attackers exploiting this vulnerability could alter site behavior, inject malicious scripts, or disrupt services by leveraging the victim's authenticated session. This threat requires organizations to review their use of the plugin, monitor for suspicious activity, and prepare for patch deployment.

For European organizations, the impact of this CSRF vulnerability can be significant, especially for those relying on the SaifuMak Add Custom Codes plugin to customize their web platforms or content management systems. Unauthorized modification of custom code can lead to injection of malicious scripts, resulting in data theft, session hijacking, or defacement. This can compromise the confidentiality and integrity of sensitive data, damage organizational reputation, and disrupt business operations. Since the vulnerability exploits authenticated sessions, attackers can bypass authentication controls indirectly, increasing the risk of privilege escalation or persistent backdoors. The availability of services could also be affected if malicious code disrupts normal operations. Organizations in sectors such as finance, healthcare, and government, where data protection is critical, face heightened risks. Additionally, regulatory compliance under GDPR mandates protection against unauthorized data access and manipulation, making exploitation of this vulnerability a potential compliance issue. The lack of known exploits currently provides a window for proactive mitigation, but the public disclosure increases the likelihood of future attacks targeting European entities using this plugin.

To mitigate CVE-2025-62739, European organizations should implement several specific measures beyond generic advice: 1) Immediately audit all instances of the SaifuMak Add Custom Codes plugin to identify affected versions and usage contexts. 2) Restrict access to the plugin’s administrative interfaces to trusted personnel only, employing strict role-based access controls. 3) Implement or verify the presence of anti-CSRF tokens in all forms and state-changing requests related to the plugin. 4) Enforce strict origin and referer header validation to ensure requests originate from legitimate sources. 5) Monitor web server and application logs for unusual POST requests or changes to custom code configurations. 6) Prepare to apply vendor patches or updates as soon as they become available, and subscribe to vendor security advisories for timely notifications. 7) Consider temporary disabling or removing the plugin if it is not essential, to eliminate the attack surface. 8) Educate users and administrators about the risks of CSRF and the importance of logging out of administrative sessions when not in use. 9) Employ web application firewalls (WAFs) with rules designed to detect and block CSRF attack patterns targeting the plugin. 10) Conduct penetration testing focused on CSRF vulnerabilities in the affected environment to validate mitigation effectiveness.