What is a Keylogger and How Does It Work

A keylogger is a sneaky piece of software that can record passwords and other information without a person realizing it. You may have heard the term “keylogger” being thrown around and wondered what it is and whether it’s helpful in PC or phone monitoring.

In fact, keylogging tools can capture every keystroke on a computer or electronic device. They can be used legitimately or maliciously. Employers may use keyloggers to monitor employees computer, and parents can monitor their kids’ devices thus.

However, malicious users can steal credit card numbers, login credentials, and other sensitive data. In 2017, the Equifax data breach became the largest ever recorded after exposing 145,500,000 consumer records.

In this article, we’ll explore what keylogger is, how to detect keylogger, the steps to take to protect yourself from keylogger software, and how to use Keylogger legally.

What is a Keystroke Logger?

A keystroke logger is a software or hardware device that records all keystrokes on an electronic device. It takes the information to a Command and Control server, where someone analyzes it and detects usernames or passwords to get into an otherwise secure device, computer, application, or program.

For a parent or employer, the information gathered on the device is demystified by an app that you can see on the dashboard of the parent website.

Are KeyLoggers Illegal?

The legalities of keyloggers depend on the circumstances of use. Not all keyloggers are illegal. If you use keylogger software with the consent of the person you intend to monitor, it’s perfectly legal. For example, an IT department can use keyloggers to troubleshoot a system or monitor employees, while parents can use them to monitor children’s devices.

However, using a keylogger as malicious software without someone’s consent is illegal and may lead to criminal charges. The August 2022 LastPass data breach resulted from a keylogger installed on an employee’s device. In 2013, eBay security system was also breached, leaking 145M user records.

Ultimately, unauthorized access to information on a person’s computer is illegal under state and federal laws. This includes illegal keylogger use.

Types of Keylogger Software

There are hardware-based and software-based keyloggers. These two types of keyloggers vary by the way they log keystrokes.

Hardware Keyloggers

Hardware keyloggers require physical access to the target device. They are embedded within the computer hardware, such as the computer cabling, keyboard, or USB. Hardware keyloggers don’t leave any traces, making them hard to detect.

Keystrokes logged by a hardware keylogger are stored in the device’s internal memory. Because of this, they are rarely used for cyberattacks and device monitoring.

Software Keyloggers

Software keyloggers do not require physical access to the device. They can be easily installed as malicious software that you download intentionally or as part of malware. Software keyloggers do not infect the computer with a virus but run in the background collecting keystrokes.

There are various types of software keyloggers:

Keystroke Keyloggers

These keyloggers capture every keystroke on a keyboard. They include:

API-Based Keyloggers

API-based keyloggers are the most common. This is because they use the keyboard API to record keystrokes. API stands for Application Programming Interface. This type of keylogger allows the software to communicate with the keyboard. They intercept all keystrokes that you input into the program you’re typing into.

API keyloggers are also called user-mode keyloggers. They intercept keyboard and mouse movements. They are the easiest to create and also the easiest to detect since they are known within the Win32 API.

Form-Grabbing Keyloggers

Form-grabbing keyloggers intercept web form submissions. They record the data you enter into a field, such as login credentials. The keylogger malware is deployed on a website, like a prompt asking you to enter your credentials such as name, email address, phone number, credit card number, etc. The information you input is submitted when you hit “Enter” or “Submit.”

Kernel-Based Keyloggers

Kernel-based keyloggers work at the core of a computer’s operating system. These keyloggers use filter drivers that intercept keystrokes as they pass through the kernel. Thus, they have admin-level permissions to everything entered into a computer system.

A kernel mode keylogger is more advanced and challenging to execute. Because of this, it is also difficult to detect within a system. In addition, it can change the internal dynamics of Windows.

Kernel mode keyloggers are distributed in various ways, including:

• opening email attachment;
• rootkits;
• malicious software bundles;
• running a file through a P2P network;
• drive-by download attack.

JavaScript-Based Keyloggers

A JavaScript-based keylogger is written in JavaScript code and injected into a website. This keylogging software can run scripts that record all keystrokes a website’s users enter. A JavaScript keylogger may require only one line of code to capture all keystrokes, including tabs backspace and carriage returns entered onto a website.

For example, if a JavaScript-based keylogger is inserted on Facebook, the person does not need to crack a password. The login credentials will be available once you log in to your Facebook account.

Acoustic Keyloggers

Acoustic keyloggers monitor the sound made by someone when they type. Every key has a signature sound and can therefore be determined by statistical analysis such as frequency analysis. Nevertheless, acoustic keyloggers are complex and rarely used. Moreover, they are time-consuming and require at least 1000 keystrokes to have a sample large enough for analysis.

Remote Access Tools

A Remote Access Tool is software that enables a user to connect and access a remote computer, network, or server. They allow the connectivity of two or more computers on separate networks. Regarding keylogging, there are Remote Access Trojans (RATs). This is software that allows remote control of a computer.

Once the RAT is on the computer, someone can send commands to the computer and receive data from that computer.

Web-Based Keyloggers

These are keyloggers that help you log user data and other keystrokes online. They are mainly used for parental and employee monitoring. Web-based keyloggers can display keystrokes logged in real-time. They can also show a history of the keystrokes logged on that particular browser.

Wireless Keyloggers

Wireless keyloggers capture data sent and received between a wireless keyboard and its receiver. The wireless keylogger can be connected to the target computer or wirelessly using a disguised device like a wall charger.

Firmware Keyloggers

A computer BIOS handles keyboard events and can be reprogrammed to record keystrokes before processing them.

How Does Keystroke Logger Work?

The keylogging process takes place in different stages as follows. The process is generally the same for phones and computers.

1. Installation Process

The installation process of keyloggers varies depending on the type of keylogger. A hardware keylogger must be installed between the keyboard and the computer or phone. The most common type, a software keylogger, can be installed by downloading the software on the target device. This can be done physically or remotely.

Some of the ways a keystroke logger can end up in your computer or mobile devices are:

Phishing attacks: This is where you get a fraudulent email that looks legitimate. Once you click on the link or attachment, the remote installable keylogger downloads to your device.

Drive-by-Download: A drive-by download installs a malware infection on your device without your consent or knowledge. This method often works through a malicious website by installing malware when you visit the site. After which, the software will collect keylogger activity and send it to the predefined destination.

Trojan Horse: These are computer programs that can perform a harmless function but are designed to breach the security of a computer. They can carry a keylogger infection as part of the downloaded software.

Web Page Scripts: A web page script can contain a keylogger code on a web page. When you visit the website or click a link, the keylogger downloads automatically.

Parental control app: A parental control app can include keylogger in its features. This enables you to see passwords of apps and sites that a child visits.

2. Capturing Keystrokes

Once the keylogger program is installed, it sits between the keyboard and the screen, capturing every keystroke in transit. It can capture keystrokes made on the computer and other input methods like touchscreens.

Keyloggers capture data in real time, and some can include the time and the keystroke that was logged alongside the program in use at that time.

Keyloggers usually have filters and can be impossible to detect. This is because they do not harm the device. The volume of information they collect also varies between software. Some of the basic private data that keyloggers collect is information typed on a website or application.

Complicated keyloggers can record everything typed, no matter the medium or platform. They can also copy and paste content.

3. Recording and Storing Data

Captured keystrokes are recorded and stored on the target device locally or remotely on a server. Depending on the keylogger and configuration, the recorded data can include webcam recordings and screenshots. Keystroke loggers on mobile devices can assemble information from apps, screenshots, microphone data, GPS, and camera capture.

4. Transmitting Data to a Remote Location

The collected data is then sent to a predefined database, website, or FTP server (file transfer protocol server). This can be done via email or peer-to-peer network. You can also remotely log into a machine and download the keystroke data. The data can be encrypted to prevent interception or detection in transit. Some keyloggers can send alerts when certain phrases or keywords are typed.

Keylogger for PCs And Cell Phones

Keyloggers have been designed for both phones and computers. The main difference between computer-based and cell phone-based keyloggers is that the latter can record more than just keystrokes. Mobile-based keyloggers can also take screenshots and access the camera and microphone.

How to Detect Keylogger and Protect Yourself

Detecting keyloggers is often a challenge since they do not affect the functioning of a device. Nevertheless, all you need to do is inspect your computer for anything unfamiliar plugged into it. Always check the back panel for anything new using a corporate desktop.

Software keyloggers can run quietly in the background without interfering with the device. However, they are telltale signs that a keylogger is in your computer or cell phone. You may notice slowed performance or lag when using the keyboard or mouse. The input does not appear on the screen as fast as it should.

Keyloggers can also degrade web performance. They may interfere with the loading of web pages or spawn unusual error messages when web browsing. On a smartphone, you may notice that your screenshots have degraded. However, visible signs of keylogging malware mean that the type of keylogger used is not well-built. A good keylogger does not cause disruptions to a computer’s operating system.

These are some of the methods you can use to detect a well-built keylogger:

1. Invest in a Powerful Antivirus that can detect a keylogger: a powerful antivirus software can scan your device, identify keystroke logging software, and block it with other forms of malware.
2. Check the Task Manager list or Activity Monitor: Your computer shows all applications and processes currently running. You can sort through this information and determine if you have a keylogger running in the background.
   • If you’re a Windows user, you will find that information in the task manager. Click Ctrl + Alt + Del on your keyboard. It will open the task manager.
   • Search for Activity Manager on Mac computers and click on it to see the current processes.
3. Scan hard disc: for recently stored files. Files that are often updated can help you identify a keylogger.
4. Clear temporary files: Temporary files are rarely checked, making them a good hiding place for keyloggers. In addition, it can be hard to find keyloggers since they are often cluttered.
   • Type “RUN” into the search bar and click Enter for Windows. Then, type %temp% in the search bar. 
   • For Mac, open the Finder app and hold down Cmd + Shift + G on your keyboard. Then type Library/Cache into the search bar.
   It’s best to clear all files from the temporary folder if you can’t find out which of the files is a keylogger.
5. Check the programs that run on the computer boot-up.

Once you’ve detected a keylogger attack, protecting your system and yourself from keyloggers is important. These are some of the best methods to do it.

How to Use Keystroke Monitoring Legally

It would be unfair not to talk about the benefits of keyloggers.

Parental Control

As a parent, you can install a keylogger on your child’s devices to monitor their online activities. This can ensure they are safe from online threats such as cyberbullying and cyber predators. A recent FBI study proves that one in seven kids has experienced unwanted sexual solicitation online.

Some things a keylogger can help with include web history monitoring, time tracking, screenshots, and connected hardware pieces. Keyloggers are not easily visible on the devices they are being used. Thus, you can use them without your kid suspecting it has been added to their device.

Keyloggers for parental monitoring can prove helpful if you’ve noticed changes in your child’s behavior and want to identify the source. They can also help track inappropriate searches, so you can get ahead of harmful content. Finally, you may locate bad company by seeing who your child communicates with and what they chat about.

Employee Monitoring

Employers may use keyloggers to monitor employee activity on company computers. This is common among companies that are keen on productivity monitoring. They can view online searches and what is typed on a computer. This can help with evaluating employee performance.

Keyloggers can prevent data breaches. According to a Haystax survey, employees and contractors are the main cause of data breaches, and the majority (56%) of security professionals say insider threats are on the rise.

Law Enforcement

Law enforcement agencies may use keyloggers as part of their investigations to gather evidence against suspects. For example, the FBI can install keylogging software into a suspect’s computer and monitor that account’s cyber activity.

The DEA (Drug Enforcement) convinced a federal judge to authorize sneaking into an Ecstasy manufacturing front to copy hard drives and install a keylogger. This information was used to acquire passwords for the cartel’s encrypted web email Hushmail.com and PGP.

Note that it’s important to comply with keyloggers’ local laws and regulations. In many countries, instilling keyloggers on someone’s device with their knowledge and consent is illegal. Using keyloggers for legitimate purposes and respecting everyone’s privacy rights is essential.