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

In a troubling development for network security, a staggering number of ASUS routers, exceeding 9,000 units, have fallen victim to a sophisticated botnet attack identified by the label “AyySSHush.” This alarming breach was uncovered in March 2025 by the cybersecurity experts at GreyNoise, highlighting the growing sophistication of cyber threats targeting household networks.

The attack takes advantage of specific authentication vulnerabilities inherent in these routers, allowing the malicious actors to leverage legitimate features for unauthorized access. Central to this infiltration is the establishment of a persistent SSH (Secure Shell) backdoor that proves incredibly resilient against conventional security measures.

What sets this attack apart is the way the backdoor is embedded within the router’s non-volatile memory (NVRAM). This embedded backdoor has the alarming ability to withstand firmware updates, meaning that even attempts to refresh or secure the router’s software fall short of eliminating the threat. As a result, traditional remediation techniques, which often include routine updates and reboots, are rendered ineffective in neutralizing this persistent risk.

Network security specialists and everyday users alike are encouraged to assess their router’s security settings and stay informed about potential vulnerabilities. With this kind of cyber threat on the rise, staying one step ahead in network protection has never been more crucial.