CVE-2025-20205 describes multiple XSS vulnerabilities in Cisco Identity Services Engine (ISE) guest portals' web management interface. The root cause is insufficient validation of user-supplied input, enabling an authenticated remote attacker with valid administrative credentials to inject malicious scripts. Successful exploitation could lead to arbitrary script execution within the context of the interface or unauthorized access to browser-based sensitive data. The vulnerabilities affect Cisco ISE versions 3.1.0, 3.2.0, 3.3.0, 3.4.0, and 3.5.0. No official remediation or patch information is provided in the available data.

An attacker with valid administrative credentials can exploit these vulnerabilities to perform cross-site scripting attacks, potentially executing arbitrary scripts in the context of the affected interface or accessing sensitive information stored in the browser. This could lead to unauthorized actions within the management interface or disclosure of sensitive data. The impact is limited by the requirement for high privileges (administrative access) and user interaction (UI required).

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, restrict administrative access to trusted personnel only and consider additional controls such as multi-factor authentication to reduce the risk of credential compromise. Monitor Cisco's advisories for updates regarding patches or official mitigations.