Crafting a Cyber Defense Strategy beyond the Perimeter: as Cyber Espionage Exploits bypass Traditional Cyber Defenses

In a new chapter to cyber technology exploitation story, U.S. cybersecurity researchers at FireEye have discovered evidence of a stealthy attack vector on Internet traffic network routers that allows cyber espionage to go undetected.  This data extraction and redirection exploit has been observed internationally in the network devices of private industries and governments across multiple continents.  The attacks have been mainly directed at routers supplied by technology world-leader Cisco, but other network device manufacturers may be targeted as well.

The attacks use a highly sophisticated form of malicious software, dubbed “SYNful Knock.”  The malware replaces the basic operating system software controlling the routers.  SYNful Knock presents all the qualities of an advanced persistent threat (APT) as it is difficult to detect and remains in place even when devices are shut down and restarted.

Network routers are very good targets for the adversary because they usually operate outside the perimeter of traditional cyber defense tools (e.g., firewalls, anti-virus software, intrusion detection/protection systems, HBSS, etc.) used by organizations to safeguard data flows.  Controlling the router allows sensitive data to be selectively redirected to unintended destinations. .

Until now, routers were considered predominantly vulnerable to only DDoS attacks.  SYNFUL Knock represents a significant APT escalation in an adversary’s ability to exploit and defeat cyber devices, tools, and technology.

This implies when forming a cyber defense strategy an organization must think beyond traditional concepts of network perimeter defense.  A “strategy” that relies on technology alone is too much of a tactical approach and limited in its ability to defeat a sophisticated adversary.  This is why strategic planning that incorporates a maturating, long range view for protecting the network based on the components of Cyber ART – Attribution, Rules of action, and Trust relationships (discussed in my earlier post) is a better approach to strategy in the long run.   Cyber ART fosters leadership aptitudes of “adaptation & improvisation” – crucial abilities for senior decision makers to think above and beyond the limitations of traditional concepts of data protection.

Additional details on the SYNful Knock exploit may be found at: