As technology companies race to fix two major vulnerabilities found in computer chips, the ways in which those chips could theoretically be targeted by hackers are becoming clear.
Collectively, Meltdown and Spectre affect billions of systems around the world – from desktop PCs to smartphones.
So why are so many different devices vulnerable – and what is being done to fix things?
What part of my computer is at risk?
When it is working, a computer shuffles around huge amounts of data as it responds to clicks, commands and key presses.
The core part of a computer’s operating system, the kernel, handles this data co-ordination job.
The kernel moves data between different sorts of memory on the chip and elsewhere in the computer.
Computers are engaged in a constant battle to make sure the data you want is in the fastest memory possible at the time you need it.
When data is in the processor’s own memory – the cache – it is managed by the processor but it is at this point that the newly revealed vulnerabilities come into effect.
Spectre essentially gets programs to perform unnecessary operations – this leaks data that should stay confidential.
Meltdown also grabs information – but it simply snoops on memory used by the kernel in a way that would not normally be possible.