5 Malicious Bots and How to Avoid Them

Learn to recognize these harmful applications

A web robot or internet robot, usually called a "bot," is a software application that performs repetitive jobs. Bots index search engines and analyze information from web services. Chatbots can even answer user questions about a product or service. While there are helpful bots, there are also malicious bots designed to infiltrate your system and steal information. Here's a look at five types of malicious bots, how to recognize them, and how to protect yourself.

Hand touching digital chat bot for provide access to information and data in online network, robot application and global connection, AI, Artificial intelligence, innovation and technology.
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Spambots and Spimbots

Spambots aim to bombard your inbox with spam messages or interrupt your instant-messaging chats with unsolicited instant messages ("spim").

Some unscrupulous advertisers use spambots to target individuals based on demographic information obtained from the user's profile. These bots are usually easy to spot because they typically don't try to engage you in conversation. Instead, they often send you a link to click on along with some hook to get you interested.

Spambots' goal is to spread spam email messages throughout the internet. At their most benign, they bombard you with unwanted ads and links. At their worst, they contain malware downloads and try to perpetuate scams.

Web robots representing spambots
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Zombie Bots

A zombie bot is a compromised computer that has become a slave to some nefarious entity who controls it along with hundreds or thousands of other computers as part of a botnet.

Cybercriminals use these zombie computers to coordinate large-scale attacks where all the zombie computers act in unison, carrying out the master botnet owner's commands. These infections can be challenging to detect and eradicate. Many owners of the zombie bot-infected computers don't even know their PCs are infected.

Zombie computers connected into a botnet
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Malicious File-Sharing Bots

Users of peer-to-peer file-sharing services have almost certainly encountered malicious file-sharing bots. These bots take the user's query term (i.e., a movie or song title) and respond to the query, stating that they have the file available and providing a link to it.

In reality, the bot takes the search query term, generates a file by the same name (or similar name), and then injects a malicious payload into the fake file. The unsuspecting user downloads it, opens it, and unknowingly infects their computer.

Concept of malicious file sharing with a computer user on one side and a malicious bot on the other end
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Malicious Chatterbots

Dating service websites and apps are often havens for malicious chatterbots. These chatterbots pretend to be a person, emulating human interaction, and often fooling humans on the other side.

Many people fall for these malicious chatterbots, not realizing they're harmful programs whose goal is to obtain personal information, including credit card numbers, from unsuspecting victims.

Girl communicating on the malicious scammer bot in a cartoon illustration
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Fraud Bots

Fraud bots are a general category that includes many types of bots that aim to scam unsuspecting people for financial gain. Many such bots are more like scripts that generate false clicks for advertisement revenue programs, create fake users for sweepstakes entries, or even generate thousands of fake votes for something that the creator is for or against.

Internet fraud bot seen in a sea of numbers
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Protect Yourself From Malicious Bots

It's essential to stay aware and vigilant when interacting on the internet. Because many antivirus programs don't detect botnet-related software, consider installing and using a "second opinion" scanner, such as Malwarebytes, to see if your primary antivirus program missed anything. Malwarebytes is updated frequently and can detect many malware forms that traditional virus scanners miss. 

Also, be very wary about clicking links or giving out personal information when chatting online with strangers, whether on a dating app or site or a social network. Even when communicating on Facebook, if you notice something odd about a question your friend asks you, call or text them to see if it's really them.