CVE-2026-25347 is a stored cross-site scripting (XSS) vulnerability found in the Acato WP REST Cache plugin for WordPress. The flaw arises due to improper neutralization of input during web page generation. Attackers can exploit this vulnerability to inject malicious JavaScript code into cached REST API responses. When an unsuspecting user accesses a compromised page, the script runs in their browser with the permissions granted to the WordPress site. This could lead to various attacks, including session hijacking, defacement, or distribution of malware. Such vulnerabilities are particularly concerning on sites with sensitive user data or high traffic, as they can compromise the integrity and confidentiality of user interactions.

To mitigate the impact of this vulnerability, administrators should ensure they are using the latest version of all WordPress plugins and regularly audit installed plugins for known security issues. Implement Content Security Policy (CSP) headers to minimize the potential effects of XSS attacks. Regularly back up site data and consider employing a Web Application Firewall (WAF) to block malicious payloads targeting XSS vulnerabilities.