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What Is Data Exfiltration?

What Is Data Exfiltration?

It always pays to know your enemy. More specifically, it pays to understand the methods of your enemies. To that end, we are going to discuss some of the specific ways in which hackers and cyber-criminals can steal data from various parties. As you probably know, the theft of data is very often the goal of cyber-crime operations. Whether that data might be personal, financial, or organizational, malicious actors have many ways to turn that data into some sort of profit. Of course, they do have to find a way to abscond with that data once it has been found.

What Is Data Exfiltration

Exfiltration is the opposite of infiltration. While infiltration involves the stealthy insertion of an asset, exfiltration involves the stealthy removal of assets. In short, it is the process of escaping with the desired data.

To understand it a little better, try to put yourself in the mindset of a data thief. You have managed to gain remote access to your target system, and you have found the data that you seek. At that point, you still have to escape with that data before it can be used. There are, unfortunately, many ways in which this can be done. There are quite a few ways to transfer data over a network, and the attacker can attempt to hijack any of these.

How Can It Be Done?

Cyber-criminals might use any number of methods, but the easiest way is to simply gain remote access to a server. Often, they can get control of a server by using its default credentials. Your server, of course, is basically a computer whose purpose is to “serve” the internet. Your internet service provider probably has hundreds or even thousands of them.

Sometimes, people fail to change the default usernames or passwords of these servers. Obviously, this is a very amateurish mistake, but such things do happen. If the hacker can gain control of the server to which you are connected, they can intercept all of your traffic. Depending on the situation, they might even be able to view all of that data in an unencrypted form. Most of the time, they will attempt to use the remote access protocol to gain control of the server. If the owner of the server forgot to disable this feature, every user could pay the price.

Downloading through a browser or a P2P application is another obvious possibility. These can send large amounts of data and can be disguised as harmless-looking downloads. Often, they will download the data to another device on the network…one that they know to be insecure. Your average mobile phone has little security, so that is one possibility. Once the data resides on an easy-to-access device, the hacker can then download it to their personal files. As if all that weren’t bad enough, some have even used cross-site scripting (XSS) as a covert transfer method.

What Kinds Of Data Are Most Likely To Be Targeted?

By understanding what the attacker is likely to want, you can make better choices about where you store your data. Usernames and passwords are obviously the most high-priority data. Not only can this let someone gain complete access to an account, but it can also allow them to compromise other accounts. They do this by taking advantage of automated password retrieval systems. Once they have control over one of your accounts, it becomes a lot easier to impersonate you.

Cryptography keys are another high-priority target, as they can allow an attacker to bypass your encryption-based passwords. In the hands of an expert, these keys are just as good as obtaining a password. You see, encryption works by scrambling your data so that it cannot be read. When the data is scrambled, it cannot simply be scrambled in a random way. If that were the case, there would be no way to decrypt the data. Encryption keys are just files that tell the computer exactly how to encrypt and decrypt.

Social security numbers and other personally-identifying information are similarly high-priority targets. These can be used for scams that involve identity theft and can be very damaging. In the case of a business-related data breach, the hackers might also be looking for sensitive information with some potential for blackmail.

How To Prevent Data Exfiltration

There are lots of security software programs that offer intrusion detection systems (often called IDS for short). These are basically smart network monitors that measure network activity against a certain baseline configuration. Any change from that baseline configuration is reported as suspicious. Obviously, you’ll get a few false positives from time to time, but this kind of software is a good step. This is one type of network monitoring, which is the best approach to prevent data exfiltration.

You also need to make sure that you store your sensitive data in secure places. In general, your data storage should be divided into three tiers:

  • Tier 1: Low risk: Can be stored anywhere except on an open network
  • Tier 2: Medium Risk: Can be stored in the cloud or on specific devices
  • Tier 3: High Risk: Store only in encrypted containers or external offline devices

You should also do everything you can to protect your temporary memory. Again, this is a software feature that can be found. It is often called “memory protection” or something similar. Basically, it blocks the use of malicious code and stops it from executing. This makes it harder for external third parties to access your memory cache.


Data exfiltration is basically the last step of a data breach attack. As such, it is likely to be your last chance to stop the attacker before they abscond with all that information. If you are not up to the task of protecting your system, then you are clearly in need of some competent computer IT services. If you are looking for a good IT support provider, we recommend you call PCH Technologies at (856) 754-7500.