Re:Intel Security Issue Update: Addressing Reboot Issues
by mtgx on Friday January 12, 2018 @07:52AM
(#16132432)
Meltdown is not a variant of Spectre. Spectre itself has two variants.
And Meltdown was the easiest to exploit. Spectre is "bad" because it affects everyone, but it's less exploitable than Intel's Meltdown.
Re:Intel Security Issue Update: Addressing Reboot Issues
by dogma1138 on Friday January 12, 2018 @08:16AM
(#16132561)
Meltdown is very much a variant of this, 3 variant exist 3.1 if you consider Meltdown on ARM.
Meltdown is the easiest to exploit and the easiest to fix it’s also the least scary one as far as compromises go.
https://www.amd.com/en/corporate/speculative-execution
https://googleprojectzero.blogspot.co.uk/2018/01/reading-pri...
It's also not the scariest variant, it's easily fixed (performance degradation aside), doesn't require a microcode update to be fixed hence is 100% software mitigated, doesn't allow you to cross between guest and host memory address spaces and isn't remotely exploitable.
On the other hand variant 1 and 2 are much scarier because they are the complete opposite of Meltdown.