Shield Security < 20.0.6 - Reflected XSS

Vulnerability

The Shield Security WordPress plugin before version 20.0.6 fails to sanitize and escape a parameter before outputting it back in the page, leading to a Reflected Cross-Site Scripting (XSS) vulnerability [1].

Exploitation

An attacker can craft a malicious URI with a payload in the vulnerable parameter. This can be sent to high-privilege users such as administrators. No authentication is required for the attacker to create the link, but user interaction (clicking the link) is needed [1].

Impact

Successful exploitation allows the attacker to execute arbitrary JavaScript in the context of the victim's browser. Because the vulnerability can be targeted at high-privilege users, an attacker could potentially perform actions as an admin, such as creating new admin accounts or modifying site settings [1].

Mitigation

The vulnerability is fixed in version 20.0.6. Users should update to this version or later [1].