What Is a Keylogger Trojan?

Some viruses can monitor all of your keystrokes

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A keylogger Trojan virus is just as it sounds: a program that logs keystrokes. The danger of one infecting your computer is that it tracks every single keystroke you enter through your keyboard, including passwords and usernames.

Why a Keylogger Trojan Virus Is so Insidious

Trojan keyloggers are installed without notice along with a regular program. Like their namesake, Trojan horse viruses don't actually look dangerous. They're attached to regular, commonly used applications.

Trojan keyloggers are sometimes called keystroke malware, keylogger viruses, and Trojan horse keyloggers.

Some businesses use programs that log keystrokes to keep track of employees' computer usage, as do various parental control programs that log a child's internet activity. These programs are technically considered keyloggers but not in the malicious sense.

What a Keylogger Trojan Does

A keylogger monitors and logs every keystroke it can identify. It stores the information locally to share with the hacker through either physical or online access.

A keylogger can record anything it's programmed to monitor. If you have a keylogger virus and you're using your keyboard to enter information anywhere, you can bet the keylogger Trojan is logging it. This is true whether you're typing in a program installed on your computer (such as Microsoft Word) or on a website (such as that for your bank or social media account).

Some keystroke malware can refrain from recording the keystrokes until a certain activity is registered. For example, the program might wait until you open your web browser and access a specific bank website before it starts.

Risk Factors

The easiest way for a keylogger Trojan to reach your computer is when antivirus software is outdated, turned off, or altogether absent. Trojan keyloggers and other viruses are always evolving into new versions with new strategies, and they'll pass right through antivirus software that doesn't recognize them.

Typically, a keylogger gets into your computer as part of an executable file of some sort, such as an .exe file. That's how any program on your computer is able to launch, though, so you can't simply avoid downloading executable files.

One thing you can do is vet your software sources carefully. Some websites are well known for scanning programs before releasing them to the public, in which case you can be certain they don't contain malware. Others are simply more prone to having keyloggers attached to them (such as torrents).

Get tips on avoiding keylogger viruses by learning how to safely download and install software.

Programs That Can Remove a Trojan Keylogger Virus

Lots of antivirus programs protect your computer against malware, including keylogger Trojans. So long as you have an updated antivirus program running, such as Avast, or AVG, you should be secure enough to thwart any keylogger attempt.

If you need to delete a keylogger you already have on your computer, however, you'll have to scan for malware manually using a program such as Malwarebytes or SUPERAntiSpyware. Another option is to use a bootable antivirus program.

Some other tools don't necessarily remove keylogger viruses but instead use an alternate input method so that the keylogger doesn't understand what you're entering. For example, the LastPass password manager can insert your passwords into a web form through a few mouse clicks, and a virtual keyboard lets you type using your mouse.