Major Cybersecurity Breach: 9,000 ASUS Routers Compromised by Botnet Attack

In a concerning development for network security, a large-scale cybersecurity breach has impacted more than 9,000 ASUS routers. This incident stems from a sophisticated botnet known as “AyySSHush,” which was brought to light by cybersecurity experts at GreyNoise in March 2025.

What makes this attack particularly alarming is its ability to exploit existing authentication vulnerabilities and leverage the features of the routers to create a persistent SSH backdoor. This backdoor is not simply a temporary flaw; it is entrenched within the router’s non-volatile memory (NVRAM). As a result, even attempts to restore the router through firmware updates or device reboots will not eliminate the threat.

This revelation underscores the critical need for robust cybersecurity measures and highlights the vulnerabilities that can exist within even widely-used devices. Users of affected ASUS routers are urged to take immediate action to secure their networks and consider alternative solutions to mitigate the risks.

Stay informed and proactive about your network security to protect against such sophisticated cyber threats.