CVE-2025-59573 is a medium-severity vulnerability classified under CWE-80, which pertains to improper neutralization of script-related HTML tags in web pages, commonly known as a basic Cross-Site Scripting (XSS) vulnerability. This vulnerability affects CozyThemes' Cozy Blocks plugin, specifically versions up to and including 2.1.29. The issue arises because the plugin fails to properly sanitize or neutralize user-supplied input that is rendered in web pages, allowing an attacker to inject malicious scripts. These scripts can execute in the context of the victim's browser, potentially leading to theft of session cookies, redirection to malicious sites, or other client-side attacks. The CVSS v3.1 base score is 5.3, indicating a medium severity level. The vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N indicates that the vulnerability is remotely exploitable over the network without any privileges or user interaction, but the impact is limited to confidentiality (partial data disclosure), with no impact on integrity or availability. No known exploits are currently reported in the wild, and no patches have been linked yet. The vulnerability was published on September 22, 2025, and was reserved on September 17, 2025. Cozy Blocks is a WordPress plugin widely used for content block management, which means this vulnerability primarily affects websites using this plugin for content creation and display.

For European organizations, this vulnerability poses a risk primarily to websites using the Cozy Blocks plugin. Exploitation could lead to unauthorized disclosure of sensitive information such as session tokens or personal data accessible via the browser, potentially facilitating further attacks like session hijacking or phishing. While the vulnerability does not directly affect data integrity or availability, the confidentiality breach can undermine user trust and violate data protection regulations such as the GDPR. Organizations in sectors with high web presence, including e-commerce, media, and public services, may face reputational damage and regulatory scrutiny if exploited. Since the vulnerability requires no user interaction and can be triggered remotely, automated scanning and exploitation attempts could increase, especially if proof-of-concept exploits emerge. However, the lack of known exploits in the wild currently limits immediate risk. Still, European organizations should be vigilant due to the widespread use of WordPress and its plugins across the continent.

1. Immediate mitigation involves updating Cozy Blocks to the latest version once a patch addressing CVE-2025-59573 is released by CozyThemes. 2. Until a patch is available, organizations should implement Web Application Firewall (WAF) rules to detect and block typical XSS payloads targeting the affected plugin's input vectors. 3. Conduct a thorough audit of all user input fields and content blocks managed by Cozy Blocks to identify and sanitize any untrusted data manually. 4. Employ Content Security Policy (CSP) headers to restrict the execution of inline scripts and reduce the impact of potential XSS attacks. 5. Monitor web server and application logs for unusual request patterns indicative of exploitation attempts. 6. Educate web administrators and developers about the vulnerability to ensure prompt response and remediation. 7. Consider isolating or disabling non-essential Cozy Blocks features that accept user input until the vulnerability is resolved. 8. Regularly back up website data to enable recovery in case of compromise.