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3
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2answers
127 views

Why are Protection Rings called rings?

Protection rings are different privilege levels granted to software, with the kernel being the most privileged, applications the least privileged, and drivers somewhere in between. My question is why ...
2
votes
1answer
71 views

How to fix Spectre variant 3a and variant 4?e

How I can fix CVE-2018-3640 [rogue system register read] aka 'Variant 3a' and CVE-2018-3639 [speculative store bypass] aka 'Variant 4'? My status for them is VULNERABLE. I have Intel CPU and using ...
1
vote
2answers
133 views

What can give physical access to CPU?

If an attacker has an unlimited physical access to CPU, but does not have access to memory, including RAM, can he attack and gain access to the user's data? I heard the opinion that this is ...
-1
votes
2answers
77 views

Extracting passwords from recycled machine using Spectre and Meltdown

With Spectre and Meltdown, hackers can extract your password from the CPU cache. If I give someone my computer without the hard drive, can he extract my passwords through the CPU?
0
votes
0answers
99 views

CPU Usage at 100% due to explorer.exe with malicious threads.

(Keep in mind I'm not a computer expert so I'm trying my best here.) Hello, recently I've had a problem with my computer causing my CPU Usage to go to 100%. This makes me unable to move/create/rename ...
1
vote
1answer
65 views

Does Speculative Store Bypass Attack Require Assembly/Source Code Knowledge?

ok, so the gist of speculative store bypass attack to my understanding is that, cpu chooses the most frequent code path, bypass the if/else test and just assumes that it's true/false and then execute ...
1
vote
1answer
102 views

Do Spectre(-NG) and Meltdown affect Mill?

Given what is publicly known about the Mill CPU, would it be affected by Spectre(-NG) or Meltdown style attacks? Why/why not?
1
vote
0answers
96 views

What Spectre V2 patches fixes which vulnerabilties on Linux?

Let's assume I have a computer with a pre-Skylake Intel processor that doesn't have microcode mitigating the Spectre V2 attack. Then to my understanding, if the kernel and all user-space applications ...
7
votes
3answers
187 views

How can CPU designers prevent information leaks from speculated execution?

We know about short-term measures to mitigate the Meltdown and Spectre vulnerabilities in certain microprocessors where speculative execution has measurable effects on cache timings (mainly patches to ...
7
votes
1answer
870 views

Intel firmware/microcode updates that make processors “immune” to both Spectre and Meltdown?

Recently Intel has claimed the following in a press release (emphasis added): SANTA CLARA, Calif., Jan. 4, 2018 — Intel has developed and is rapidly issuing updates for all types of Intel-based ...
6
votes
2answers
483 views

Capability of microcode hacking?

Before Spectre and Meltdown, I've never heard of users updating microcode on a chip through firmware or otherwise. I actually thought it was written into the silicon and immutable. Now I'm seeing a ...
0
votes
0answers
82 views

Why is spectre and meltdown affecting all cpu architectures? [duplicate]

My question is regarding the recent issue of meltdown and spectre that has affected "all" processors. Initially I though it was just x86_64 architecture based processors. So when they said it affects ...
11
votes
2answers
477 views

Does recent Intel hardware mitigate Meltdown at the hardware level?

Recently a security researcher made the following claim via Twitter (emphasis added): If you're running Windows, I'm about to publish a tool that checks if you have the "Variant 3: rogue data cache ...
5
votes
2answers
898 views

Are VIA CPUs vulnerable to Spectre/Meltdown attacks?

I couldn't find any information about the recently published Spectre/Meltdown attacks affecting VIA CPUs. Are they also affected by this vulnerabilities?
5
votes
1answer
440 views

What was state of the art knowledge on security of speculative evaluation when it was introduced to Intel CPUs?

Many sources claim that almost all Intel x86 CPUs back to Pentium Pro are vulnerable to the Meltdown attack. Pentium Pro was introduced to the market in 1995. What was the state of the art knowledge ...
4
votes
3answers
655 views

Do the Spectre and Meltdown CPU bugs affect AMD in addition to Intel?

If a server or or PC is running AMD CPUs, will those be affected by the Spectre and/or Meltdown bugs currently effecting Intel chips? Why or why not? What makes it affect one and not the other? How ...
1
vote
2answers
447 views

How does the Intel CPU design flaw affect us? [closed]

Today, I saw this in the news. I'm hesitant to install the fix, because I've heard it would slow down IO 50%, which is not acceptable for me. But a guy said that the flaw allows JavaScript in the ...
3
votes
1answer
270 views

Does the main OS run “virtualised” under the ring -1 hypervisor?

After reading this answer which explains that modern CPUs have a ring -1 that is running a hypervisor on the CPU and handles vmenter & stuff, I am wondering: The main operating system, like the ...
5
votes
3answers
430 views

Understanding the scope of Intel hyperthreading errata KBL095

Recently, many motherboards supporting skylake or kabylake, got a uefi update described as cpu microcode security update for a specific Intel errata, described by Intel as : Short Loops Which Use ...
2
votes
1answer
576 views

Intel Management Engine vulnerabilities in CPUs without vPro

Intel Management Engine (ME) imposes a security risk (see here for example). As I understand ME is a part of Intel vPro. Does having an Intel CPU without vPro support mean ME is not fully functional ...
1
vote
0answers
198 views

Frequent heavy CPU load from firefox browser -> malware? [closed]

Since recently I started to get very heavy CPU load on my 64bit Debian 9.0 Cinnamon machine. I have all my packages up to date including Firefox-ESR. Often the load is so heavy that I can hear my CPU. ...
0
votes
3answers
245 views

Can OS protect us from backdoored CPU? [closed]

I was wondering if O.S. can act in such a way to hide from CPU what it is doing? I know that everything is computed only in CPU, but O.S. decides what that is, and keeps track of file system, etc. For ...