CVE-2025-4099 is a stored cross-site scripting vulnerability in the List Children WordPress plugin (versions up to and including 2.1). The flaw is due to improper neutralization of input during web page generation, specifically insufficient input sanitization and output escaping in the 'list_children' shortcode attributes. Authenticated attackers with contributor or higher privileges can inject arbitrary web scripts that execute in the context of users viewing the injected pages, potentially leading to session hijacking or other script-based attacks. The vulnerability has a CVSS 3.1 base score of 6.4 (medium severity), with an attack vector of network, low attack complexity, requiring privileges, no user interaction, and scope changed.

An authenticated attacker with contributor-level access or higher can exploit this vulnerability to inject and store malicious scripts in pages using the vulnerable shortcode. These scripts execute in the browsers of users who view the affected pages, potentially leading to information disclosure or session hijacking. The impact is limited to confidentiality and integrity with no direct availability impact. 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 released, restrict contributor-level access to trusted users only and consider disabling or removing the List Children plugin if possible. Monitor for updates from the plugin vendor or WordPress security advisories to apply an official patch once available.