A major cyber-attack caused digital havoc when it targeted the NHS and many business services across the UK last week. The ransomware known as WannaCrypt maliciously took advantage of a security vulnerability found on 200,000 computers in more than 150 countries worldwide. Once a PC is infected, all files are encrypted by the ransomware and locked behind a paywall, forcing the user to comply or risk losing their files.
On Friday, Microsoft urged customers on all Windows operating systems, including those on unsupported systems such as Windows XP, Windows 8 and Windows Server 2003, to apply the MS17-010 hotfix update as soon as possible.This has been available since March and it’s imperative that you apply it manually, if you don’t have automated Windows Updates running on your computer.
The attack exploits a vulnerability in older Windows operating systems, namely:
Windows Server 2003
If you’re using a more recent version of Windows — and you’ve stayed up up-to-date on your system updates — you should not be vulnerable to the current iteration of the WannaCry ransomware:
Windows Server 2008
Windows Server 2008 R2
Windows Server 2012
Windows Server 2012 R2
Windows Server 2016
People running supported versions of the operating system will have received the security update MS17-010 in March. If customers have automatic updates enabled or have installed the update, they are protected. For other customers, we encourage them to install the update as soon as possible.
Provided you keep your computer updated with security updates, you should be fixing any holes that these infections exploit. The issue comes with the older, unsupported operating systems and/or those which don’t receive automatic updates, which are therefore more susceptible to attack as each year passes.
There are several other ways you can protect yourself against future ransomware attacks, but don’t assume that your antivirus offers protection against ransomware. Some of the big suites have added ransomware protection recently, but it’s unlikely to be included in an old/free package.
If it’s not, or you’re pretty sure you don’t have any kind of safeguard beyond your patched version of Windows, you can install a dedicated anti-ransomware utility.
If you have already been hit by WannaCry, then there are a number of decryption tools available. Avast has released a number of free ransomware decryption tools, that can help decrypt files encrypted by a range of different ransomware infections.