Cisco Wireless Residential Gateway products have a security vulnerability in the web server that could allow a remote attacker to hijack the devices remotely. The bug is about as serious as they come, giving remote, unauthenticated attackers access to the affected machines. The vulnerability was reported by Chris Watts of Tech Analysis to Cisco. Cisco has released and distributed free software updates to its service provider customers that address the vulnerability, the service providers would further pass-on to affected home and small office customers. The customers are advised to contact their service providers to confirm the software.
Source: https://thehackernews.com/2014/07/multiple-cisco-wireless-gateway-hacking.html