What is a remote access trojan? Everything you need to know about RATs

What is a remote access trojan?

Cybercriminals use a remote access trojan (RAT) to access and remotely control the user’s computer. RATs are spread through phishing emails or malicious websites, and once installed, they allow the attacker to access the victim’s files, steal sensitive data, and monitor user behavior. Such trojans are often used in targeted attacks and can be difficult to detect and remove.

How does a remote access trojan work?

Remote access trojans (RAT) infect a target computer or device through a phishing email or malicious website. A RAT provides an attacker with a very high level of access and remote control over a compromised system. Once malware is installed, the attacker can establish a connection with the device. This connection in the end allows the cybercriminal to remotely control the infected machine and access and steal sensitive information.

Once the RAT software is in a victims device, the attacker can perform a variety of actions, such as:

• Log keystrokes
• Take screenshots
• Access files and folders
• Control the camera and microphone
• Use the infected machine as a proxy to launch attacks on other devices
• Download and install additional malware

RATs also often use techniques such as process hollowing, code injection, or code obfuscation to avoid detection by antivirus software, making it difficult for victims to detect and remove the malware.

RATs are often used in targeted attacks and are not a common form of malware. If you get infected, removing it as soon as possible is essential to avoid data loss and other unauthorized actions.

The threat of remote access trojans

The threat of remote access trojans (RAT) is significant because they allow attackers to remotely control and access infected computers or devices, steal sensitive information, and perform various malicious actions.

Let’s take a closer look at the RAT dangers:

• Confidential data loss. The attackers use RATs to steal sensitive personal and financial data, login credentials, and intellectual property.
• Privacy invasion. RATs allow the attacker to access the user’s computer camera and microphone. They can monitor user behavior, secretly record and listen to conversations, or even blackmail.
• Network compromise. The attacker can use an infected device to launch attacks on other devices connected to the same network.
• Damage to reputation. Cybercriminals use RATs to spread false information, launch spam campaigns, or perform other actions that can damage an organization’s reputation.
• Cryptocurrency mining. Sometimes attackers mine cryptocurrency through infected computers and generate significant earnings by spreading RATs across multiple devices.
• Threat to distributed denial of service attacks. A RAT installed on multiple victim computers can be used to launch a DDoS attack. The attacker overflows a targeted server with large amounts of requests to overwhelm it and prevent it from responding to legitimate requests.

Additionally, attackers can use RATs as a stepping stone to gain access to more extensive networks, carry out more complex attacks, steal even more sensitive information, or disrupt operations of critical services, such as water supply or electricity.

Common infection methods for remote access trojans

A remote access trojan (RAT) can infect computer systems in many different ways. A seemingly innocent video game download or a click on a link in a phishing email can become a real burden. Here are some of the methods attackers use to infect their victims' devices:

• Phishing emails. RATs can sneak into devices as attachments or downloads via links in phishing emails that trick the user into clicking on them.
• Social engineering. Attackers use social engineering manipulation to convince users to download and install the RAT on their devices.
• Software vulnerabilities. Cybercriminals exploit software vulnerabilities to install RATs and gain complete administrative control to an infected system without the user’s knowledge.
• Drive-by downloads. Attackers can install RATs into devices through drive-by downloads. Users who visit a compromised website may automatically download and install a RAT on their device.
• Downloading cracked software. Users may install RAT malware into their devices by downloading cracked software, such as remote access tools, or video games from illegal websites.

Remote access trojan examples

Cybercriminals use remote access trojans (RAT) for malicious purposes such as stealing personal information, spying on users, and remotely controlling infected devices. Some RATs have been around for a long time and don’t do much harm anymore. Others are well-established and operate without your knowledge. The following are some of the known RATs:

• Poison Ivy. First discovered in 2005, Poison Ivy sneaks into devices through malicious email attachments, corrupt USB drives, or by exploiting software vulnerabilities. It is capable of keylogging, remote desktop, and port forwarding. Attackers may also exploit the infected computer and use it as a proxy server to remain anonymous while browsing the web.
• Back Orifice. One of the best-known RATs, it has been exploiting victims' devices since 1998, and was created by a hacker group called Cult of the Dead Cow. It was built as a proof-of-concept tool to exploit the vulnerabilities of the Windows operating system. Back Orifice is an old trojan, and the insecurities it exploited have been fixed. However, it is essential to stay vigilant.
• Sakula. A remote access trojan, it is associated with the hacking group known as Deep Panda or APT19. The malware has been used in targeted attacks against government agencies, defense contractors, and technology companies.
• KjW0rm. This sophisticated malware is difficult to detect in Windows systems and by antivirus. Since 2017, KjW0rm has targeted government and military organizations in the Middle East and Asia.
• Blackshades. This malicious software operates on social networks. It sends infected links to the user’s contacts and infects computer systems. The altered machines create a botnet that attackers use to launch DDoS attacks.

How to protect yourself from remote access trojans?

Remote access trojans RATs operate silently and often invisibly, so you must take security measures to prevent malware from entering your device and spreading further. Here are some safety measures you can take:

• Keep your software updated. Ensure your software is up to date to avoid hackers exploiting software vulnerabilities and infecting your devices.
• Use an antivirus program and other cybersecurity tools. Update your antivirus and firewall system regularly and run system scans from time to time. This way, you will detect unwanted and harmful viruses in time before they do irreversible damage.
• Beware of phishing emails. Phishing emails are one of the primary methods attackers use to distribute RATs. They send out emails often containing malicious attachments or links to infected web pages, opening the back door for the malware. Be wary of suspicious emails from unknown senders.
• Use a VPN. VPN services like NordVPN encrypt your browsing traffic and can help to protect your online activities from being monitored or intercepted by attackers.
• Pay attention to your system’s behavior. RATs often enter devices without the user noticing, so keep an eye out for suspicious activity. If you see any unusual activity or unexpected changes on your system, there is a chance that your computer has been infected with malware.
• Get an attachment filter. NordVPN’s additional security solution, Threat Protection Pro, is designed to protect you from downloading malware onto your device. It’s a security feature that keeps you safe when browsing and protects you from malware. This tool scans your downloads and blocks malicious content before it infects your device.
• Use multi-factor authentication. This is an additional security solution that requires more than one authentication method. Besides a password, the system requires authentication of different categories, such as a fingerprint, security token, or SMS code. The idea is that multi-factor authentication makes it more difficult for an attacker to get into a system.
• Use intrusion detection systems. A type of security software designed to detect unauthorized access or malicious activity on a device or system. Intrusion detection systems monitor network traffic, logs, and system activities and indicates an intrusion or attack.