CVE-2025-12475 is a stored cross-site scripting vulnerability in the Blocksy Companion WordPress plugin (up to version 2.1.14). It affects the 'blocksy_newsletter_subscribe' shortcode due to improper input sanitization and output escaping of user-supplied shortcode attributes. Authenticated users with contributor-level permissions or higher can inject arbitrary JavaScript code that executes in the context of other users viewing the injected pages. This vulnerability can lead to information disclosure or session hijacking. The CVSS 3.1 base score is 6.4 (medium severity), with an attack vector of network, low attack complexity, privileges required at the low level, no user interaction needed, and impacts confidentiality and integrity with no impact on availability. No patch or official remediation guidance is currently documented.

Successful exploitation allows authenticated users with contributor or higher privileges to inject and execute arbitrary scripts in the context of other users visiting the affected pages. This can lead to theft of sensitive information such as cookies or session tokens, unauthorized actions performed on behalf of users, and potential compromise of user accounts. The vulnerability does not affect availability. There are no known exploits in the wild at this time.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, restrict contributor-level access to trusted users only and consider disabling or removing the 'blocksy_newsletter_subscribe' shortcode if feasible. Monitor vendor channels for updates and apply patches promptly once released.