Security – Mettle Networks Blog

One Infected Router, a Thousand Blocked Customers

October 23, 2026 by akz

A picture showing the concept: One infected router/CPE with a subscriber taints the NAT pool of the operator, eventually affecting anther 1,000 subscribers.

On a CGNAT network, hundreds of subscribers share each public IPv4 address, so they also share its reputation. When one infected device starts sending spam, the shared address is blocklisted and everyone behind it pays. Hexium vBNG contains the offender with one standard RADIUS attribute, Framed-Pool, and a single CoA, without touching the customer’s router. … Read more

While Waiting for the Next DNSChanger

July 14, 2012July 11, 2012 by akz

Hijacking DNS look up is not a new attack vector. Massive DNS hijacking instances were observed a decade ago. But DNSChanger botnet was known to be the largest in terms of number of computers affected. This article explains the DNS hijacking attack technique in general, possible measures to prevent it and a technique to detect … Read more