This vulnerability in AddonMaster Post Grid Master (up to version 3.4.8) is a stored cross-site scripting (CWE-79) issue caused by improper input neutralization during web page generation. An attacker with low privileges can inject malicious scripts that execute when other users view the affected content, potentially leading to partial compromise of confidentiality, integrity, and availability. The CVSS 3.1 base score is 6.5, reflecting network attack vector, low attack complexity, required privileges, user interaction, and a scope change.

Successful exploitation allows an attacker to execute arbitrary scripts in the context of the victim's browser, potentially leading to information disclosure, session hijacking, or other impacts on confidentiality, integrity, and availability. The CVSS vector indicates partial impacts to all three security properties. 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, consider restricting user input capabilities and applying web application firewall (WAF) rules to detect and block malicious payloads related to XSS in the affected plugin. Monitor vendor channels for updates.