The EmbedPress WordPress plugin suffers from a stored cross-site scripting vulnerability due to improper neutralization of input in the 'id' parameter. Authenticated users with contributor or higher privileges can inject arbitrary scripts into pages, which execute upon page access by other users. This vulnerability is present in all versions up to and including 3.9.16. The CVSS 3.1 base score is 6.4, reflecting network attack vector, low attack complexity, privileges required, no user interaction, and impacts on confidentiality and integrity but not availability.

An attacker with contributor-level access or higher can exploit this vulnerability to inject malicious scripts that execute in the context of other users viewing the compromised page. This can lead to unauthorized actions such as session hijacking or data theft limited to the confidentiality and integrity of the affected users. There is no indication of availability impact. No known exploits in the wild have been reported.

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 EmbedPress plugin if possible. Monitor for updates from the vendor and apply patches promptly once available.