CVE-2025-58610 is a stored Cross-site Scripting (XSS) vulnerability classified under CWE-79, affecting the WP Chill Gallery PhotoBlocks WordPress plugin versions up to 1.3.1. The vulnerability arises from improper neutralization of user-supplied input during web page generation, allowing malicious scripts to be injected and stored within the plugin's data. When a victim views the affected page, the malicious script executes in their browser context. The CVSS v3.1 score is 6.5, indicating a medium severity level. The vector details (AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:L) show that the attack can be performed remotely over the network with low attack complexity, requires low privileges (authenticated user), and user interaction (such as viewing a page) is necessary. The vulnerability impacts confidentiality, integrity, and availability to a limited extent, as the attacker can execute arbitrary scripts that may steal session cookies, perform actions on behalf of the user, or deface content. The scope is changed (S:C), meaning the vulnerability affects resources beyond the initially vulnerable component. No known exploits are currently in the wild, and no patches have been linked yet. This vulnerability specifically targets the Gallery PhotoBlocks plugin, which is used to create photo galleries on WordPress sites, potentially affecting websites that rely on this plugin for media display and user interaction.

For European organizations, this vulnerability poses a risk primarily to websites using the Gallery PhotoBlocks plugin, especially those with authenticated users such as content managers or subscribers. Exploitation could lead to session hijacking, unauthorized actions performed with user privileges, or defacement of web content, undermining user trust and potentially exposing sensitive information. Organizations in sectors like media, e-commerce, education, and government that use WordPress extensively for public-facing or internal portals may face reputational damage and compliance risks under GDPR if personal data is compromised. The stored nature of the XSS increases risk as malicious payloads persist and can affect multiple users over time. Although the vulnerability requires low privileges, it still necessitates an authenticated user, which somewhat limits the attack surface but does not eliminate risk in environments with multiple user roles. The medium severity suggests that while the threat is significant, it is not critical, but organizations should prioritize remediation to prevent escalation or chaining with other vulnerabilities.

European organizations should immediately audit their WordPress installations to identify the presence of the Gallery PhotoBlocks plugin and its version. Until an official patch is released, consider disabling or uninstalling the plugin if it is not essential. For sites requiring the plugin, restrict user roles to minimize the number of authenticated users who can input data into the plugin. Implement Web Application Firewall (WAF) rules to detect and block common XSS payloads targeting the plugin's input fields. Employ Content Security Policy (CSP) headers to limit the execution of unauthorized scripts. Regularly monitor logs for suspicious activity related to the plugin. Educate content managers and users about the risk of XSS and safe browsing practices. Once a patch becomes available, apply it promptly and verify the fix. Additionally, conduct penetration testing focused on stored XSS vectors within the plugin to ensure no residual vulnerabilities remain.