CVE-2025-64367 identifies a stored Cross-site Scripting (XSS) vulnerability in the Adrian Tobey Groundhogg plugin, a marketing automation tool commonly used with WordPress. The vulnerability exists due to improper neutralization of user-supplied input during web page generation, which allows malicious scripts to be stored and later executed in the context of users viewing the affected pages. This can lead to unauthorized actions such as session hijacking, defacement, or redirection to malicious sites. The vulnerability affects all versions up to and including 4.2.6. Exploitation requires an attacker to have low-level privileges (PR:L) and user interaction (UI:R), such as tricking a user into clicking a crafted link or viewing a malicious page. The CVSS v3.1 base score is 6.5, indicating a medium severity with network attack vector (AV:N), low attack complexity (AC:L), and scope change (S:C), meaning the impact extends beyond the vulnerable component. The confidentiality, integrity, and availability impacts are all rated low but combined can lead to significant risk. No public exploits are known at this time, and no patches have been explicitly linked, suggesting that vendors or users should monitor for updates. The vulnerability is particularly relevant to organizations relying on Groundhogg for customer engagement and marketing workflows, as exploitation could compromise sensitive customer data or disrupt operations.

For European organizations, the impact of CVE-2025-64367 can be significant, especially for those using Groundhogg in their marketing automation infrastructure. Exploitation could lead to unauthorized access to user sessions, leakage of sensitive customer or organizational data, and potential manipulation of marketing content or workflows. This could damage brand reputation, lead to regulatory non-compliance (e.g., GDPR violations due to data exposure), and disrupt business continuity. The requirement for low privileges and user interaction lowers the barrier for exploitation, increasing risk in environments with many users or external collaborators. Given the interconnected nature of marketing platforms, a successful attack could propagate further into internal systems or third-party integrations. The medium severity rating suggests that while the threat is not critical, it warrants prompt attention to prevent escalation or exploitation in targeted attacks.

European organizations should implement the following specific mitigations: 1) Immediately monitor for and apply any security patches or updates released by Adrian Tobey or the Groundhogg development team addressing this vulnerability. 2) Enforce strict input validation and output encoding within Groundhogg configurations and any custom extensions to prevent injection of malicious scripts. 3) Limit user privileges to the minimum necessary, especially for users who can input or manage content within Groundhogg, to reduce the attack surface. 4) Educate users about the risks of interacting with suspicious links or content that could trigger XSS attacks. 5) Implement Content Security Policy (CSP) headers to restrict the execution of unauthorized scripts in browsers. 6) Monitor logs and web traffic for unusual activity indicative of XSS exploitation attempts. 7) Consider isolating marketing automation platforms from critical internal networks to contain potential breaches. 8) Regularly audit and review Groundhogg plugin usage and configurations to ensure compliance with security best practices.