A vulnerability in the web-based management interface of Cisco SPA122 ATA with Router Devices could allow an unauthenticated, adjacent attacker to conduct cross-site scripting attacks. The vulnerability is due to insufficient validation of user-supplied input by the web-based management interface of the affected software. An attacker could exploit this vulnerability by sending malicious input to the affected software through crafted DHCP requests, and then persuading a user to click a crafted link. A successful exploit could allow the attacker to execute arbitrary script code in the context of the affected interface or access sensitive, browser-based information.
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20191016-spa-dhcp-xss