CVE-2024-13851 is a stored cross-site scripting vulnerability in the Modal Portfolio plugin for WordPress, affecting all versions up to and including 1.7.4.2. The root cause is improper neutralization of input during web page generation, allowing authenticated administrators to inject arbitrary scripts. The vulnerability manifests in multi-site environments or where unfiltered_html is disabled, enabling script execution in users' browsers upon page access. The CVSS 3.1 base score is 5.5, reflecting network attack vector, low attack complexity, high privileges required, no user interaction, and partial impact on confidentiality and integrity.

An attacker with Administrator-level access can inject malicious scripts that execute in the context of users visiting the affected pages. This can lead to partial confidentiality and integrity compromise of user data or session information. The vulnerability does not impact availability. Exploitation requires high privileges and affects multi-site or restricted unfiltered_html configurations only. No known active exploitation has been reported.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is released, restrict Administrator-level access to trusted users only and consider disabling or limiting use of the Modal Portfolio plugin in multi-site environments or where unfiltered_html is disabled. Monitor vendor channels for updates and apply patches promptly once available.