Modern routers Routers have long ceased to be simple devices for distributing internet, having transformed into fully-fledged mini-computers with their own operating systems. This makes them a prime target for cybercriminals who inject malicious code to steal data or use your network in botnets. Scanning your router for viruses is a critical procedure that many users ignore until they completely lose control of their network.
Symptoms of infection can be subtle, ranging from slow internet speeds to periodic redirects to advertising sites when attempting to access familiar resources. Unlike computers, routers rarely have antivirus software installed, so online check It often comes down to analyzing DNS settings and open ports. Understanding how malware operates will help you protect your home network from most threats.
In this article, we'll explore not only automated diagnostic methods but also manual methods for identifying hidden threats. You'll learn how to distinguish a system failure from a hacker attack and what steps to take to completely clean a device. Your network's security depends on regular maintenance and access control.
Symptoms of a router infection with malware
The first sign that something is wrong with yours WiFi router Something's wrong: an unexplained slowdown in connection speed. If your provider doesn't report maintenance, and the speed drops even on wired connections, you should be wary. Viruses often use the connection to send spam or participate in DDoS attacks, which puts a huge strain on the device's processor.
Another warning sign is a change in the browser's home page or the appearance of intrusive ads on sites where they weren't previously present. This is a classic sign. DNS hijacker, which redirects your requests to fake servers. The user may not even notice that the entered bank password is going straight to the scammers.
⚠️ Caution: If the indicators on the router body are flashing rapidly when no device is active, this may indicate background data transfer by malware.
It's also worth checking the list of connected clients in the admin panel. If you see unfamiliar devices there, someone has gained access to your network. This could be the result of a virus that has shared your WiFi password with neighbors or botnets.
Online services for checking network security
You can check your router for viruses online using specialized web resources that scan for open ports and vulnerabilities. One of the most popular tools is ShieldsUP! GRC, which allows you to see which ports on your router are visible from the external network. Closed ports are the key to security, while open ones can become an entry point for attackers.
Another useful resource is Qualys SSL Labs, which checks the encryption quality and SSL/TLS configuration if your router supports remote management via HTTPS. While this isn't a direct virus check, weak cryptography is often associated with compromised devices. There are also services like F-Secure Router Checker, analyzing DNS settings for redirects.
It's important to understand that online scanners don't have access to your router's file system. They can only detect external signs of infection, such as open ports or modified DNS servers. For a thorough scan, you should use built-in diagnostic tools or manually check the settings.
Manually checking DNS and DHCP settings
The most effective way to detect a virus on a router is to check the settings. DNS serversMalware often replaces the default ISP addresses with its own to control your traffic. You can access the settings by entering the router's IP address in the browser's address bar, which is usually 192.168.0.1 or 192.168.1.1.
After logging in, find the section responsible for network or WAN settings. This should show automatic DNS settings or addresses provided by your ISP. If you see unknown IP addresses there, especially foreign ones, this is a sure sign of infection.
Also check the settings DHCP serversMake sure your router is distributing the correct gateway and DNS addresses to clients. Viruses can spoof these values to infect all connected devices, even smartphones and TVs.
☑️ DNS Security Check
Analyzing the list of connected devices
Regularly monitoring the list of connected clients is a simple yet powerful protection method. Visit the section Wireless or WiFi -> Client List (the name may differ depending on the model) TP-Link, ASUS, D-Link). Compare the list of MAC addresses with the gadgets you have.
An unknown device may indicate that your WiFi password has been compromised or stolen. In some cases, viruses disguise themselves as system devices, using similar names. If you've detected an "unwanted" guest, immediately block it using a MAC address filter and change your WiFi password to a strong one.
Pay attention to device activity. Some advanced viruses can simulate activity even if the actual device is turned off. Constant data exchange with an unknown IP address within the local network warrants a thorough diagnosis.
Table of common threats to routers
Understanding the types of threats helps you choose the right protection method. Below is a table of the main types of malware that infect network equipment and their characteristic features.
| Threat type | Penetration method | Consequences | Detection method |
|---|---|---|---|
| DNS Changer | Exploiting web interface vulnerabilities | Redirection to phishing sites | Checking DNS settings |
| Botnet (Mirai) | Guessing weak default passwords | Participation in DDoS attacks | High CPU load, open ports |
| Rootkit | Replacing the firmware | Full control over the device | Unstable operation, inability to reset |
| Adware | Deployment scripts | Intrusive advertising | Pop-ups on all devices |
What is a botnet?
A botnet is a network of infected computers and devices controlled by a hacker. Your router can become part of such a network and be used to attack other servers without your knowledge.
Methods for removing viruses and restoring them
If the check reveals any problems, the first step should be a full factory reset (Hard Reset). To do this, there's a small hole on the router body with a button that needs to be held for 10-15 seconds while the power is on. This will remove any malicious configuration.
After the reset, it's crucial to update the firmware. Visit the official website of your model's manufacturer (Zyxel, Keenetic, Xiaomi) and download the latest version of the software. Updates often contain security patches that close the holes through which the virus entered the system.
⚠️ Warning: Never download firmware from third-party websites or forums. Use only official sources, as modified versions may contain backdoors.
After reinstalling the software, be sure to change the factory administrator password to a complex and unique one. Also, disable the WPS, as it is one of the most vulnerable entry points for malicious users. The Remote Management setting should also be disabled unless absolutely necessary.
Prevention of re-infection
Securing your router is an ongoing process. Check for firmware updates regularly, at least once a quarter. Many modern models, such as Keenetic or ASUS, have an automatic update feature that is worth activating.
Use complex passwords not only for WiFi but also for logging into the router's web interface. Passwords must contain at least 12 characters, including uppercase and lowercase letters and numbers. Don't use the same passwords on different devices.
Disable unnecessary features, such as UPnP, unless you use them for games or specific applications. Fewer services running means fewer potential attack surfaces.
☑️ Monthly security checkup
Is it possible to check the router using an antivirus on a computer?
No, computer antivirus software scans the PC's file system, not the router's. It may detect the virus's network activity, but it won't be able to remove it from the router.
Will the virus reset the settings after a reboot?
Regular viruses live in RAM and disappear after a reboot, but modern threats can write themselves into permanent memory. Therefore, a full reset using the Reset button is necessary.
How often should I change my WiFi password?
It is recommended to change your WiFi password every 3-6 months, especially if you frequently have guests connecting to your network or you suspect a data leak.
Is open port 8080 on a router dangerous?
Yes, open ports, especially non-standard ones like 8080, are often used for remote control and can be used by hackers to penetrate the network.