As we mentioned in the previous sessions, IoCs are crucial important for a proactive threat hunting process. Threat hunters should know most of the information of newly threats and implement them to their hunting processes. Pyramid of Pain classifies IoCs and helps us understand better the usefulness of them.
The pyramid of pain was created by David Bianco (Fireeye). He also has a Youtube video for presenting it.
This pyramid classifies the IoCs and with going up the pyramid, IoCs help us more to detect the suspicious. Also, as we go up, it is harder to obtain these IoCs. Now, lets check these IoC types shortly;
Hash Values: A hash value is a unique identifies of the data. In theory, the hash value of each data is expected to be unique to itself. So, it gets easier to identify a data, file with its hash value. As an example, you can see below the hash values (both md5 and sha256) of openvpn.exe.
Hash values are at the bottom of the pyramid because it is very easy to change a file’s hash value and if you do not have the newly changed hash, that means you cannot detect this file anymore.
IP Addresses: IP blacklists still used by many different products, however it is also easy to change the IP address for an attacker. So, it is again does not help much to detect an adversary.
Domain Names: Everyday we can see that attackers can obtain new domain names very fast and can continue their attacks with ever changing domain names.
Network/Host Artifacts: These are the clues that adversaries left on the pc or network. These can be registery keys, processes, user agent strings, etc. Surely, to obtain such information, a forensic analysis need to be done in compromised pcs or networks.
Tools: Adversaries have their favorite tool to attacks, like pentesters have. It is important to know the tool that your enemy using and if you are good at detecting these tools, you can easily detect the attack or this situation forces the attackers use some other tools. This situation will slow down the attack and will save your time.
TTPs: Tactics, techniques and procedures are the patterns of activities or methods of a specific threat actor. As you all know, you can find all TTPs in the Mitre’s website and they are the most valuable data to identify an attack. If you know the TTPs of your enemy, it means you know what to check for a possible attack and mitigate.