AMD admits that Zen 3 CPUs are vulnerable to a new Spectre-style attack

hahahanoobs

Posts: 3,352   +1,511
No! Responsible reporting shouldn’t force the reader to google for the pertinent information... that’s just lazy reporting!

And as you can read from the replies below mine, there IS information available - the author just couldn’t be bothered to include it.
I got the jist of it just fine.
 

ZedRM

Posts: 447   +251
When it comes to Spectre and admin rights. Spectre does not need to break boundaries like Meltdown. One example, POC Spectre working on web browser using Javascript https://leaky.page/
Again, that understanding is flawed. That "example" is little more than a concept of how a Spectre exploit MIGHT work. The catch with that example is that it only works within the browser instance and then only under certain conditions. It can not be made to access data outside the browser memory space and then only within a certain memory space inside that memory stack. Change browsers and things are different. The front page of that site states this clearly. That code example can NOT be used to acquire any data that would be useful, nor can it be altered to do so. It is not a valid example of a working exploit, nor is it a "proof of concept". There is no functional merit present there.

Spectre works without admin rights, just like is should according to whitepaper.
The whitepaper says no such thing.
 

amghwk

Posts: 1,042   +959
Where's that guy who swears by his Windows XP PC that he has ZERO virus issues with his XP machine because he is extremely knowledgeable about how to protect his XP machine online.

Maybe he's a troll, but it's hillarious reading his hardline comments.
 

HardReset

Posts: 1,109   +688
Again, that understanding is flawed. That "example" is little more than a concept of how a Spectre exploit MIGHT work. The catch with that example is that it only works within the browser instance. It can not be made to access data outside the browser memory space and then only within a certain memory space inside that memory stack. That code example can NOT be used to acquire any data that would be useful. It is not a valid example of a working exploit, nor is it a "proof of concept". There is no functional merit present there.
That's not how Spectre might work, that is how Spectre works. It works without admin rights like it should. Like I said before, admin rights will help Spectre to extract data from other processes too. But Spectre functionality remains same: for reason it stays within process memory space it does not need admin rights.

So Spectre does work without admin rights, although severity is limited but it will still work. Meltdown does not work at all without admin rights.
The whitepaper says no such thing.
Whitepaper does not say any reason why Spectre would need admin rights to work.
 

scavengerspc

Posts: 1,163   +1,100
TechSpot Elite
Can't remember the last time Windows Defender threw up a false positive. It usually happens if you download cracks for games and certain activators and similar software from questionable source. If Windows improved in one area, this would be it. Windows getting viruses all the time is a meme.
I can't believe it still lives anywhere honestly. It has been a long time since any Windows 10 built-in AV has not been considered an excellent alternative. And best of all we don't need to worry about it digging its roots so far in our computers and choking them off since it's seamless.
 

Markoni35

Posts: 1,075   +442
Of course that performance impact is negligible. You could see from the stratosphere that it's a deliberate flaw. As soon as AMD became popular, they had to introduce the same security hole as Intel had.

Just think of it, during normal execution a memory address is compared to the table of pages available to the process, and this is almost instant. Now, why not use the identical pure-hardware mechanism for speculative address check? Explanation: "because it's too slow". LOL. If it was so slow it would slow down normal program execution. It's the same freaking hardware module. It's almost instant.

On top of that, the speculative and out-of-order instruction execution has more time, since nothing yet depends on it. And sometimes the entire calculation is thrown away in the end, depending on the actual program flow. Which means, even less impact on the performance.

The only reason they want people to keep using memory access without a proper check is to keep the security hole open.