A major international cyber-attack at the end of last week brought the NHS to its knees and affected computers around the world. As well as demonstrating that cyber-attacks are one of the key security issues facing the UK, it also raises important questions about the technological efficacy of Trident.

Here’s what we know so far:

  • As a result of a global cyber-attack, hundreds of computers in the NHS were infected with ‘Ransomware’ which encrypts software and files until a ransom is paid.
  • The computers affected were running the Windows XP operating system which was released in 2001 and for which no upgrades have been issued for eight years.
  • The submarines which carry Britain’s Trident nuclear weapons system also run on a variant of Windows XP.
  • The decision to install ‘Windows for Submarines’ was made instead of using a more expensive operating system.
  • It is thought to have saved around £22 million over the lifetime of the software.
  • Experts say that the system is most vulnerable to attack in its initial development and when the submarines are in dock and go ‘online’ for upgrades.
  • When asked about this on BBC One, Defence Secretary Michael Fallon said the government wouldn’t comment but reaffirmed his “faith” in Trident.

Here are the questions the government needs to answer:

  • Why was a cheaper “off-the-shelf” operating system installed during the upgrade of the submarines in 2008?
  • What precautions are taken to ensure that systems are not vulnerable during construction and installation?
  • What plans are there to upgrade the operating systems used by the submarines?
  • What precautions are taken during the submarines’ maintenance at to ensure that security is not compromised?
  • Will a variant of Windows XP be used in the new generation of Trident submarines?