A recent cyberattack has compromised thousands of TP-Link routers, turning them into a botnet which spreads malware and launches cyberattacks worldwide.

Cybersecurity researchers have discovered a widespread attack where threat actors exploited a vulnerability (CVE-2023-1389) in TP-Link Archer AX-21 routers. This security flaw allows attackers to take control of unpatched routers remotely, recruiting them – alongside thousands of others – into part of a botnet. What’s a botnet? Well, luckily Ophtek is here to explain: a botnet is a network of infected devices used for malicious activities on a huge scale.

At least 6,000 routers have been affected, with compromised devices being found all across the world in Brazil, Poland, the UK, Bulgaria, and Turkey. Once one of the TP-Link routers are infected, they can spread malware to other devices on the same network or be used as part of a coordinated botnet attack.

How Were the TP-Link Routers Exploited?

The threat-actors behind the attack started by simply scanning the internet for any vulnerable TP-Link routers that had not been updated with the latest security patches. Each time a router was found with the vulnerability in place, the attackers were able to exploit a remote code execution flaw – which allowed the hackers to install malware on the router.

Once infected, these routers became part of the Ballista botnet, which the threat actors were able to control remotely. As more and more routers, and devices connected to them, were recruited, Ballista became even more powerful. This enabled it to spread malware to further PCs and devices, launch DDoS attacks to flood websites and disrupt online services, and steal sensitive data passing through the router.

Why Should PC Users be Concerned?

All modern PCs rely on routers to connect to the internet and internal IT infrastructures, but many people take them for granted and don’t consider them a security risk. Accordingly, many PC users have been caught out by not updating their router’s firmware or keeping their device’s default password, both of which make them easy targets for hackers. As TP-Link router users have discovered, an infected router can quickly become a major security risk, sending data to hackers without the user being aware.

Keeping Your Router Safe from Vulnerabilities

It’s highly likely that you own a router or regularly use a computer connected to one. Regardless of the make and model, all routers have the potential to be compromised by threat actors. Here’s how you can stay safe:

For more ways to secure and optimize your business technology, contact your local IT professionals.

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Strong passwords are vital to cybersecurity. A recent botnet attack highlights the serious risks of relying on default passwords instead of secure alternatives.

The Mirai malware, first detected in 2016, has been behind numerous botnet attacks in the past and has been very busy recently. A botnet attack gives a threat actor control over a large number of compromised PCs, allowing the threat actor to combine these infected PCs into a formidable strike force. These attacks often involve data theft, cryptojacking, brute force attacks, and phishing campaigns.

This latest attack was enabled by the presence of default passwords on routers manufactured by Juniper Networks. Default passwords are used on many devices, so it’s important to understand the mechanics behind this attack.

Mirai Starts Infecting Routers

The exploitation of Juniper routers began in mid-December. Customers accessing the internet with Juniper Session Smart routers began to notice unusual behavior with them. The Mirai malware was seen to be scanning specifically for these routers. Once this model of router was found, Mirai proceeded to compromise the router before utilizing it in a distributed-denial-of-service (DDoS) attack.

But what was unique about the Session Smart router? Why was Mirai singling this router out? Well, the answer proved to be simple: it was a router known to ship with a default password. Therefore, a threat actor could easily take control of the router if its password hadn’t been changed. Scan enough Session Smart routers and, eventually, one will be found with the default password still in place.

The main impact of a DDoS attack is a slowdown in PC performance, as all the PC’s resources are being directed into the attack. For a business, this is troubling as the majority of their PCs are likely to be dependent on similar routers. This means that this slowdown in productivity could have a major impact on a business’ performance.

Don’t Fall Victim to Default Passwords

Users of Session Smart routers have been advised to change their password from the default version to a unique and strong one. This is the best advice you can give when it comes to default passwords. Leaving them in place is simply inviting threat actors into your networks. However, there are further measures you can take to secure your devices:

  • Educate Users About Risks: Train your employees to understand the dangers of default passwords. Make sure they understand what is and isn’t a secure password, helping to build a culture of cybersecurity awareness.
  • Use Multifactor Authentication: The beauty of multifactor authentication is that it adds an extra layer of security to your defenses. Therefore, even if one of your passwords is compromised, additional authentication is required to access your devices and networks.
  • Monitor for Default Password Usage: It’s difficult to monitor every device and verify the status of its password, but you can get help with this. Many security tools – such as Kaspersky Industrial CyberSecurity for Networks – can scan devices connected to a network and determine if a default password is being used.

For more ways to secure and optimize your business technology, contact your local IT professionals.

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