CVE-2025-70545 describes a stored XSS vulnerability in the web management interface of the PPC (Belden) ONT 2K05X router with firmware version v1.1.9_206L. The CGI component fails to properly sanitize user input, enabling remote unauthenticated attackers to inject JavaScript code that is stored persistently. This code executes upon access to the interface, leading to potential compromise of user session confidentiality and integrity. The vulnerability has a CVSS v3.1 base score of 6.1, indicating medium severity, with attack vector network, low attack complexity, no privileges required, user interaction required, scope changed, and low impact on confidentiality and integrity, no impact on availability. No exploits in the wild or patches are currently documented.

Successful exploitation allows remote unauthenticated attackers to execute arbitrary JavaScript in the context of the router's web management interface. This can lead to disclosure of sensitive information or manipulation of the interface by hijacking user sessions or injecting malicious content. The impact affects confidentiality and integrity but does not affect availability. The scope of the vulnerability is changed, meaning the attacker can affect resources beyond their initial privileges.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, restrict access to the router's web management interface to trusted networks and users only. Consider disabling remote management if not required. Monitor for updates from the vendor regarding patches or official mitigations.