Posts Tagged 'Wannacrypt'

Lessons from Wannacrypt and its cousins

Now that the dust has settled a bit, we can look at the Wannacrypt ransomware, and the other malware  that are exploiting the same vulnerability, more objectively.

First, the reason that this attack vector existed is because Microsoft, a long time ago, made a mistake in a file sharing protocol. It was (apparently) exploited by the NSA, and then by others with less good intentions, but the vulnerability is all down to Microsoft.

There are three pools of vulnerable computers that played a role in spreading the Wannacrypt worm, as well as falling victim to it.

  1. Enterprise computers which were not being updated in a timely way because it was too complicated to maintain all of their other software systems at the same time. When Microsoft issues a patch, bad actors immediately try to reverse engineer it to work out what vulnerability it addresses. The last time I heard someone from Microsoft Security talk about this, they estimated it took about 3 days for this to happen. If you hadn’t updated in that time, you were vulnerable to an attack that the patch would have prevented. Many businesses evaluated the risk of updating in a timely way as greater than the risk of disruption because of an interaction of the patch with their running systems — but they may now have to re-evaluate that calculus!
  2. Computers running XP for perfectly rational reasons. Microsoft stopped supporting XP because they wanted people to buy new versions of their operating system (and often new hardware to be able to run it), but there are many, many people in the world for whom a computer running XP was a perfectly serviceable product, and who will continue to run it as long as their hardware keeps working. The software industry continues to get away with failing to warrant their products as fit for purpose, but it wouldn’t work in other industries. Imagine the discovery that the locks on a car stopped working after 5 years — could a manufacturer get away with claiming that the car was no longer supported? (Microsoft did, in this instance, release a patch for XP, but well after the fact.)
  3. Computers running unregistered versions of Microsoft operating systems (which therefore do not get updates). Here Microsoft is culpable for an opposite reason. People can run an unregistered version for years and years, provided they’re willing to re-install it periodically. It’s technically possible to prevent (or make much more difficult) this kind of serial illegality.

The analogy is with public health. When there’s a large pool of unvaccinated people, the risk to everyone increases. Microsoft’s business decisions make the pool of ‘unvaccinated’ computers much larger than it needs to be. And while this pool is out there, there will always be bad actors who can find a use for the computers it contains.

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