What Is a Keylogger? Detect, Remove, and Prevent

Hackers continue to find new ways to steal data and monitor victims. One of these ways is through keylogger software, which monitors victims’ keyboards and records everything they type. In this article, learn how to detect, remove, and prevent a keylogger from infiltrating your device and keeping track of all that you do.

What is a keylogger?

A keylogger is a type of malware that monitors keystrokes on a computer and records every keystroke. It tracks the personal information it collects. Because it has access to everything a user types into their keyboard, it can monitor a user’s bank logins, Social Security number, and passwords, among other private information.

Keyloggers do have legitimate uses; IT services, for example, may use them to troubleshoot technological issues. However, people often use them for malicious purposes. Cybercriminals employ keyloggers to get information about their victims which can be used against them in the future.

Three types of keylogger software

There are two kinds of keyloggers: keylogger software and keylogger hardware. Of the two, keylogger software is much more common, as it’s harder for victims to detect and easier for hackers to place. Not all keystroke monitoring software works the same way, however. There are three categories of software that users should be aware of: API-based keyloggers, kernel-based keyloggers, and form grabbing-based keyloggers.

API-based keyloggers

A graphic illustrating the data that keyloggers can steal

API-based (application programming interface-based) keystroke monitors are the most common keylogger software. Keyboard API interception allows hackers to capture each key you type and log the data, meaning they can essentially piece together anything that the user has typed.

Kernel-based keyloggers

Kernel-based software impedes the target device's kernel, or core operating system. These are one of the most difficult types to detect because of how they interact with the computer’s operating system, but they are also rarer than other software types. Like API-based keyloggers, kernel-based keyloggers record keystrokes to capture anything typed on a computer.

Form grabbing-based keyloggers

Form grabbing-based loggers capture data from web forms, like login or signup forms online. The hacker has access to any sensitive information on the form. This could include your name, phone number, bank information, address, or Social Security number. Like all keystroke monitoring software, the process is almost undetectable; the interception happens right as the user submits a form.

How to detect keyloggers

Malicious keyloggers are difficult to detect, as they are either installed without the user’s knowledge or accidentally downloaded by the user themselves. Hackers commonly use root kits or Trojan horse malware to infiltrate a user’s computer with keylogger software.

However, detecting keylogging software is not impossible. Look out for signs that your computer has a malware infection; if it runs slowly, crashes frequently, or hosts an increasing number of popups, malware – and more specifically, keylogger malware – could be the cause.

For mobile devices, watch out for a quickly-draining battery, random bouts of turning on and off, and strange messages in your texts or inbox. These all indicate a malware infection on a phone.

You can also use an antivirus or antimalware program to detect malicious software and other issues. Run periodic scans to ensure that your device is healthy; if you do have keystroke monitoring software, these scans will detect it.

How to remove keyloggers

The most efficient way to remove keyloggers is through an antivirus software program. Downloading an antivirus program with anti-malware scan and removal features will detect, and subsequently remove, any keyloggers found on your device.

You can also search for foreign programs in Task Manager or Activity Monitor, depending on whether you have a Windows or Mac device. If you find any programs that you did not install, right-click the program and select Uninstall or Uninstall/Change. Follow the prompts until you remove the program.

How to prevent keyloggers

To prevent keyloggers, consider employing these tactics:

  • Use two-factor authentication. Two-factor authentication is a great way to protect online accounts. Should your device be compromised by a keylogger, it could prevent someone from logging into your accounts, as they would need a second login code sent only to your phone or email.
  • Don’t click on unfamiliar links. If you click foreign links from strange emails, social media direct messages, or text messages, you can download malware without realizing it.
  • Only download secure files. Many of these programs piggyback off of other files downloaded from the web. Make sure anything you download is only from a secure, HTTPS site.
  • Use an antivirus defender program. As mentioned earlier, using antivirus software protects your computer against threats. Using antivirus software like Norton can stop keyloggers and other forms of malware before they take root.

Practicing these prevention tactics will help keep your device safe against not just keylogging threats but also other viruses.

How to use keyloggers legally

If you have a legitimate reason for using a keylogger, like monitoring your child’s screen time or tracking employees’ work as an IT professional, you can purchase and install the software on your own.

There are free keyloggers available for public use in these cases. Refog and Kidlogger both offer free software online for monitoring employee or child screen time and activity. These programs aren’t invisible like malicious keyloggers, so the user might be able to detect them. However, if you use them legitimately and the user knows they’re being monitored, these monitoring apps shouldn’t be an issue.

If you need a keylogger for iPhone or iOS devices, FlexiSPY is a comprehensive one used for employee monitoring and parental control on iPhones and iPads. However, it requires jailbreaking the device. This may cause other problems that can't be fixed even by resetting the iPad or iPhone. If jailbreaking the device isn’t an option, WebWatcher is an alternative that monitors similar device activity.

Spyine is a trusted keylogger app for Android phones; it works remotely and doesn’t require the device to be jailbroken. Users can also monitor their own device in real time and check for unauthorized use with this spy app.

To use this kind of software legally, make sure the person you’re tracking is aware that they are being monitored. In addition, download the software to the device from a secure website to ensure you don’t inadvertently download malware along with the keylogger.