The most effective cyberattack is the one you can’t detect. Process injection allows an infiltrator to hide in plain sight.
Realizing that an attack vector has been running in your network right under your nose can be shocking. You played your part by implementing what seemed like effective security defenses, but the attacker managed to bypass them anyway. How was that possible?
They could have deployed process injection by inserting malicious codes into your legitimate processes. How does process injection work, and how can you prevent it?
What Is Process Injection?
Process injection is a process whereby an attacker injects malicious codes into a legitimate and live process in a network. Prevalent with malware attacks, it allows cyber actors to infect systems in the most unassuming ways. An advanced cyberattack technique, the intruder inserts malware into your valid processes and enjoys the privileges of those processes.
How Does Process Injection Work?
The most effective kinds of attacks are those that can run in the background without raising suspicion. Normally, you could detect a malware threat by outlining and examining all the processes in your network. But detecting process injection isn’t so easy because the codes hide under the shadows of your legitimate processes.
Since you have whitelisted your authorized processes, your detection systems will certify them to be valid with no indication that something is amiss. Injected processes also bypass disk forensics because the malicious codes run in the memory of the licit process.
The attacker uses the invisibility of the codes to access all aspects of your network that the legitimate processes they are hiding under can access. This includes certain administrative privileges that you wouldn’t grant just about anyone.
Although process injection can easily go unnoticed, advanced security systems can detect them. So, cybercriminals raise the bar by executing it in the most unassuming ways that such systems will overlook. They use basic Windows processes like cmd.exe, msbuild.exe, explorer.exe, etc. to launch such attacks.
3 Process Injection Techniques
There are different process injection techniques for different purposes. Since cyber threat actors are very knowledgeable about various systems and their security standing, they deploy the most suitable technique to increase their success rate. Let’s look at some of them.
1. DLL Injection
DLL (Dynamic Link Library) injection is a process injection technique in which the hacker uses a dynamic link library to impact an executable process, forcing it to behave in ways you didn’t intend or expect.
The attack injects the code with the intent of it overriding the original code in your system and controlling it remotely.
Compatible with several programs, DLL injection allows the programs to use the code multiple times without losing validity. For a DLL injection process to be successful, the malware must contain data of the contaminated DLL file in your network.
2. PE Injection
A Portable Execution (PE) is a process injection method where an attacker infects a valid and active process in your network with a harmful PE image. It’s simpler than other process injection techniques as it doesn’t require shell coding skills. Attackers can easily write the PE code in basic C++.
PE injection is diskless. The malware doesn’t need to copy its data onto any disk before the injection begins.
3. Process Hollowing
Process Hollowing is a process injection technique where, instead of making use of an existing legitimate process, the attacker creates a new process but infects it with malicious code. The attacker develops the new process as a svchost.exe file or notepad. That way, you won’t find it suspicious even if you were to discover it on your process list.
The new malicious process doesn’t start running immediately. The cybercriminal makes it inactive, connects it to the legitimate process, and creates space for it in the system’s memory.
Process injection can wreck your entire network as the attacker could have the highest level of access. You make their work a lot easier if the injected processes are privy to your most valued assets. This is one attack you must strive to prevent if you aren’t ready to lose control of your system.
Here are some of the most effective ways to prevent process injection.
How Can You Prevent Process Injection?
1. Adopt Whitelisting
Whitelisting is the process of listing a set of applications that can enter your network based on your security assessment. You must have deemed the items on your whitelist harmless, and unless incoming traffic falls within the coverage of your whitelist, they can’t pass through.
To prevent process injection with whitelisting, you must also add user input to your whitelist. There must be a set of input that is allowed to pass through your security checks. So, if an attacker makes any input outside your jurisdiction, the system will block them out.
2. Monitor Processes
In as much as a process injection can bypass some security checks, you can turn it around by paying close attention to the process behavior. To do this, you must first outline the expected performance of a specific process and then compare it with its current performance.
The presence of malicious codes in a process will cause some changes, no matter how little they may be to a process. Normally, you would overlook those changes because they are insignificant. But when you are keen on discovering differences between the expected performance and current performance via process monitoring, you’ll notice the anomaly.
3. Encode Output
Cyber threat actors often use Cross-Site Scripting (XSS) to inject dangerous codes in a process injection. These codes turn into scripts that run in the background of your network without your knowledge. You can prevent that from happening by vetting and cleaning all suspicious inputs. In turn, they’ll be displayed as data and not malicious codes as intended.
Output encoding works best with HTML encoding—a technique that enables you to encode variable output. You identify some special characters and replace them with alternatives.
Prevent Process Injection With Intelligence-Driven Security
Process injection creates a smokescreen that covers up malicious codes within a valid and operational process. What you see isn’t what you get. Attackers understand the efficacy of this technique and continuously use it to exploit users.
To combat process injections, you have to outsmart the attacker by being not-so-obvious with your defenses. Implement security measures that will be invisible on the surface. They will think they are playing you, but without them knowing, you are the one playing them.
