Threat attribution is the process of identifying actors behind an attack, their sponsors, and their motivations. It typically involves forensic analysis to find evidence, also known as indicators of compromise (IOCs), and derive intelligence from them.
Obviously, a lack of evidence or too little of it will make attribution much more difficult, even speculative. But the opposite is just as true, and one should not assume that an abundance of IOCs will translate into an easy path to attribution.
Let’s take a simple fictional example to illustrate:
François is the chief information security officer (CISO) at a large US electric company that has just suffered a breach. François’ IT department has found a malicious rootkit on a server which, after careful examination, shows that it was compiled on a system that supported pinyin characters.
In addition, the intrusion detection system (IDS) logs show that the attacker may have been using an IP address located in China to exfiltrate data. The egress communications show connections to a server in Hong Kong that took place over a weekend with several archives containing blueprints for a new billion-dollar project getting leaked.
The logical conclusion might be that François’ company was compromised by Chinese hackers stealing industrial secrets. After all, strong evidence points in that direction and the motives make perfect sense, given many documented precedents.
This is one of the issues with attribution in that evidence can be crafted in such a way that it points to a likely attacker, in order to hide the real perpetrator’s identity. To continue with our example, the attacker was in fact another US company and direct competitor. The rootkit was bought on an underground forum and the server used to exfiltrate data was vulnerable to a SQL injection, and had been taken over by the actual threat actor as a relay point.
Another common problem leading to erroneous attribution is when the wrong IOCs have been collected or when they come with little context. How can leaders make a sound decision with flawed or limited information?
Failing to properly attribute a threat to the right adversary can have moderate to more serious consequences. Chasing down the wrong perpetrator can result in wasted resources, not to mention being blinded to the more pressing danger.
But threat attribution is also a geopolitical tool where flawed IOCs can come in handy to make assumptions and have an acceptable motive to apply economic sanctions. Alternatively, it can also be convenient to refute strong IOCs and a clear threat actor under the pretext that attribution is a useless exercise.
Despite its numerous pitfalls, threat attribution remains an important part of any incident response plan. The famous “know your enemy” quote from the ancient Chinese general Sun Tzu, is often cited when it comes to computer security to illustrate that defending against the unknown can be challenging. IOCs can help us bridge that gap by telling us if attackers are simply opportunistic or are the ones you did not expect.