Patient Zero Day

Hospitals are used to dealing with viruses, from the common cold to a variety of tropical diseases there are procedures in place to diagnose, isolate and treat patients. What is more challenging to them is dealing with digital infections, which can wreak havoc and cause the digital realm to endanger people’s lives.

Recently Melbourne Health’s networks were infected by a new variant of the Qbot malware strain. This slightly obscure malware also known as Qakbot has been used by Russian hackers since 2009 and specialises in infecting older machines using unknown or unpatched flaws. In this case Melbourne Health’s older Windows XP machines seem to be patient zero in the outbreak. As any doctor will tell you an aging population and new virus strains from abroad is a pandemic waiting to happen.

The health sector are not the only ones keeping Windows XP on life support, the British Navy still rely on Windows XP for their fleet of nuclear submarines. In an unfortunate twist for Melbourne Health, the Qbot malware, although entering by a zero day XP exploit, was actually built to target Windows 7 causing the unfortunate side effect of disabling infected XP systems.

In our malware labs we have recently encountered several compromised websites delivering Qbot via the Rig Exploit Kit. These attacks have been using either a known Flash exploit or an unknown IE exploit to download and run the Qbot malware on the victim's machine. Interestingly the malware has advanced a lot recently and contains a number of tricks to bypass AV and avoid analysis including erasing itself if it is run in a virtual machine.

With enterprise AV unable to detect these threats what can be done to protect the endpoints and the patients? Let’s take some medical advice:

• Isolate potential contagions – Vulnerable groups are usually the first to fall ill so focus on the browser, plugins and document viewers first. Web content such as websites, documents and plugins should be kept in isolation where possible. If we can contain a threat it cannot spread.
• Screen and test – We can verify that some applications are known to be in the clear and not infected so we can allow list them. Start with your employees first by allow listing your standard corporate build and this will make the process much easier. Any new applications that appear can then be easily blocked until they are tested and given the all clear.
• Give the right medicine in the right dose – Make sure that users have the appropriate privileges, don’t prescribe the same admin rights for everyone. Giving admin rights to a user facing malware threats is like giving steroids to treat an infection, you lower the systems defences and the infection takes over. Qbot relies on admin rights to disable security features and embed itself.

With these proactive defence strategies you can secure endpoints against even advanced zero day attacks without relying on detection. So be proactive today and keep the malware away.