What is a malicious IP and how to protect yourself against it

What is a malicious IP?

A malicious IP is the internet protocol of a device that has a known association with malware or spam. For example, it can be a server or a computer that hosts viruses, performs phishing campaigns, or is part of a botnet. Cybersecurity systems often blacklist these IP addresses to make it easier for firewalls and other cybersecurity tools to recognize potential threats and prevent them from accessing your network. A malicious IP doesn’t necessarily mean that the device’s owner is a cybercriminal. Instead, it works as a warning to your system, alerting it to the presence of an infected or compromised device that could lead to threats like data theft or system compromise. 

What are the types of malicious IPs? 

You could find at least 20 different types of malicious IPs online (including fake IP addresses). However, let’s stick with some of the most popular ones.  

Botnet IPs

These IPs are assigned to devices that are part of a botnet — a network of computers controlled by (typically) one cybercriminal (also known as botmaster). Malicious actors use botnets to launch phishing attacks, send spam emails, or perform DDoS attacks.

Malware distribution IPs

Malware distribution IPs describe devices that threat actors may use to spread malware such as ransomware or viruses. Because of these devices, you may encounter infected email attachments, malicious downloads, or exploit kits.

Remote access trojan (RAT) IPs

Some computers may be infected with RAT, allowing attackers to remotely control hijacked systems. Malicious actors use RATs to steal data, install malware, or lay the groundwork for other cyberattacks (for example, using infected computers to gain access to other systems).

Scamming IPs

Scamming IPs (sometimes also known as phony tech support IPs) belong to fraudsters who pose as tech support workers or other service personnel. Scamming IP owners may try to trick their targets into installing malicious software or providing sensitive information.

Anonymous proxy IPs

These types of malicious IPs describe proxy servers cybercriminals use to mask the origin of their malicious activities. Threat actors may leverage anonymous proxies to hide their identity or bypass geolocation restrictions.

Fraudulent website IPs

Fraudulent website IPs are associated with web pages that offer counterfeit goods and fake services or engage in online scams (such as fake job offers). These websites can often host malware, such as browser session hijackers or SQL-injection software.

Scanner IPs

These malicious IPs belong to devices that are or have been involved in any kind of attempt to scan or otherwise penetrate other domains. Devices with malicious scanner IPs search for system vulnerabilities to provide threat actors with potential attack vectors.

As you may have noticed, malicious IPs are linked to devices that can be used for any type of cyberattack. Along with the already mentioned IPs, you may also encounter DDoS, port scanning, SQL injection, and phishing IP addresses.

How to identify a malicious IP

To identify a malicious IP, you can check its reputation. It may be a little-known fact to some internet users, but IP addresses, like people, have a reputation (known as IP reputation). Cybersecurity companies keep blacklists of malicious or suspicious IPs that have been associated with such cybercrimes as brute force attacks or phishing campaigns. Firewalls, antivirus software, and other anti-malware tools use these IP reputation lists to help users and systems identify and block malicious IPs before they can reach your network.

While online security tools are reliable in detecting malicious IPs, you can also do a manual check, for your peace of mind. Online IP lookup websites allow users to verify the reputation of an IP address or check systems for unusual activity, such as unexpected network traffic or unusual logins. If you notice a suspicious IP in your network activity, you should inspect it, and take appropriate action.

What should I do if I detect a malicious IP?

If you detect a malicious IP you should follow this set of steps:

• Block the malicious IP immediately. Most firewalls allow users to manually block IPs. You can also use an antivirus. However, regardless of which one you choose, take this step immediately after detecting a malicious IP.
• Investigate the source of the IP. Once you block the malicious IP, you can use online IP lookup tools to determine who owns the IP address. This can help you understand whether the IP is part of a known botnet or if it's associated with specific types of cyberattacks.
• Keep an eye out for suspicious activity. Review your network traffic for unusual login attempts or spikes in traffic. Those could be the signs of an ongoing attack. Additionally, you can look for clues (for example, a “sign-in was blocked because it came from an IP address with malicious activity” notification) indicating attempted data exfiltration, malware installations, or compromised accounts. For easier network scanning and monitoring, you can use intrusion detection systems (IDS) or intrusion prevention systems (IPS).
• Update your software. Make sure that all your firewalls, online security tools (such as antivirus), and operating systems are up to date. You can also look over your security configurations (double-check passwords and two-factor authentication [2FA] on your accounts) to see if everything’s in order.
• Notify interested parties. If you have detected a malicious IP on your work computer (or a personal computer that you may sometimes use for work), notify your company’s IT department. It’ll be able to track the IP address and better prepare for potential attacks, preventing additional cyber threats. Also, it’s a nice and professional thing to do.

How to protect against malicious IPs

Protecting against malicious IPs is a feat that requires some effort. However, it can be relatively simple if you follow the tips below.

For businesses

To safeguard your company from malicious IPs you should do the following:

• Implement firewalls and IP blocking. Setting up firewalls to block known malicious IPs is a basic cybersecurity practice for mitigating this cyber risk. You can implement IPS to prevent known malicious traffic from entering your network.
• Utilize threat intelligence. Threat intelligence is a field of cybersecurity that constantly monitors and updates potential cyber threats. Integrating threat intelligence services into your network security systems will offer updated blacklists of known malicious IP addresses and help to block traffic from suspicious sources automatically.
• Consider using geo-blocking and regional restrictions. If your business doesn’t operate in certain regions, you can think about restricting traffic from IPs located in them. While a bit unorthodox, such a measure is a reasonable choice for companies that are susceptible to attacks from nation-sponsored threat actors (for example, government agencies or large businesses).
• Constantly monitor and update your systems. It may sound like a no-brainer, but keeping up with the system updates is a vital part of protecting against malicious IPs and other cyber threats. Regular testing, monitoring, and updating can help your company reduce its attack surface and address the system’s cyber vulnerabilities before malicious actors can exploit them.

For individuals

Here are some tips for private users on how to protect yourself from malicious IPs:

• Use antivirus software with IP blocking. That is one of the easiest ways to safeguard yourself from malicious IPs without doing much manual work.
• Regularly update your software and operating system. System and software updates often include the latest security patches, designed to protect users from evolving cyber threats. Ignoring them wouldn’t be wise from a cybersecurity perspective.
• Avoid clicking suspicious links. Malicious IPs are often associated with IP spoofing and phishing campaigns, so be sure to avoid clicking them. Otherwise, you’ll be at risk of exposing yourself to malware or data theft.
• Use a VPN. A VPN allows you to change your IP address and encrypt your internet traffic, making it much harder for malicious IPs to target your device. Using services such as NordVPN comes with additional online security benefits, such as the Threat Protection Pro™ feature. Threat Protection Pro™ takes care of your online safety by blocking access to malicious websites and scanning files for malware as they’re being downloaded.

While it may not seem like a big deal, malicious actors can do a lot of damage with your IP address. Therefore you should be careful when browsing online and seriously address threats such as malicious IP addresses.