Hajime is a ‘white worm’ that infects and secures vulnerable IoT devices

The Internet of Things (IoT) has been a source of some serious security concerns recently, with millions of IoT devices being vulnerable to attack and compromise. Mirai is perhaps the most famous of all IoT malware, and it was at the root of an attack in October 2016 that took down a significant portion of the Internet.

Now, there’s another piece of code that’s targeting IoT devices, and it’s growing. The strange thing, however, is that as far as anyone can tell, the so-called “Hajime” code isn’t doing anything bad, and in fact, it might be doing some good, as Symantec’s Security Response blog reports.

Researchers have known about Hajime since October 2016, and the software is like Mirai in that it targets IoT devices with open Telnet ports and secured with the factory default username and password credentials. Hajime, therefore, uses the same attack vector as the destructive malware that was responsible for the massive distributed denial of service (DDoS) attack last year.

What makes Hajime different is that it appears to contain no destructive code, and it’s actually even more stealthy and effective at hiding itself than Mirai. Hajime also utilizes a peer-to-peer network as opposed to relying on a single command and control (C&C) server. Oddly enough, the latter characteristic makes Hajime more robust and harder to shut down than Mirai, because there’s not a single server to locate and eradicate.

However, the only active thing Hajime does at this point is to display a message every 10 minutes or so, which is currently limited to saying, “Just a white hat, securing some systems. Important messages will be signed like this. Hajime Author. Contact CLOSED. Stay Sharp!” Researchers note that the message is cryptographically signed and requires a hardcoded key, and so it’s clear where the message comes from.

Perhaps more important, Hajime also takes steps to lock down the IoT devices it infects, blocking a few ports that have been identified as making devices vulnerable to attack. In essence, the Hajime code helps to secure IoT devices and given its fast growth rates is actively securing the internet at large.

Symantec

Of course, there’s no guarantee that Hajime’s author actually has good intentions. The reality is that Hajime is making things safer today, but it remains a piece of code that’s architected in such a way as to make it a relatively trivial matter to switch over to nefarious purposes.

In addition, these “white hat hacking” attempts and “white worms,” as they’re called, are temporary — reboot the device and they go away. They’re not like firmware updates that would have a lasting effect. Therefore, devices could be infected with Mirai one day, then “fixed” with Hajime the next, and then further “fixed” with one of the other white hack efforts that have attempted to clean up the IoT security mess.

In the long run, what’s needed is for IoT users to lock down their devices with strong passwords, and to shut off Telnet login and use SSH where they can. Router security can be strengthened by turning off Universal Plug and Play (UPnP), and all devices should be kept up to date with the latest firmware updates. Until users and manufacturers do their part to lock down IoT, however, it will remain something of a wild, wild west where black and white hat hackers battle for control.