CVE-2026-13458 describes a stored Cross-Site Scripting vulnerability in the GenerateBlocks WordPress plugin (edge22) affecting all versions up to and including 2.3.0. The vulnerability is due to improper neutralization of input during web page generation (CWE-79). Authenticated attackers with contributor-level privileges can inject arbitrary web scripts by placing dynamic tags such as {{post_meta key:...}} in HTML attributes like title, aria-label, alt, or data-* attributes. By setting the corresponding post meta key to a value containing a closing quote and an injected event-handler attribute via the Custom Fields metabox, attackers can cause script execution when the page is viewed. The CVSS 3.1 base score is 6.4 (medium severity) with network attack vector, low attack complexity, low privileges required, no user interaction, and impacts on confidentiality and integrity but not availability.

An attacker with contributor-level access or higher can inject malicious JavaScript code into pages generated by the plugin, which will execute in the context of any user viewing those pages. This can lead to unauthorized actions, data theft, or session hijacking. The vulnerability affects confidentiality and integrity but does not impact 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 avoid using dynamic tags in HTML attributes that reference untrusted post meta keys. Monitor vendor channels for updates and apply patches promptly once released.