Super User
Super User

Questions tagged [meltdown]

Use for questions related to CPU hardware issue (common on Intel CPUs) which was discovered in mid 2017 and became public in January 2018 - CVE-20175754

Meltdown is a hardware issue affecting almost all CPUs from 2013 onwards (as of Jan 2018) There is no fix for the problem, however there are OS workarounds which disable KPTI, which may have a performance impact depending on the type of load.

The core of the issue has to do with the way Intel CPUs make guesses about what instructions are going to be executed (branch prediction). By carefully timing operations it is possible for a program to infer information about areas of RAM it should not have access to.

This can lead to passwords/pass phrases/keys being stolen. It is primarily a problem in virtualised environments - unknown parties get access to a single VM may be able to infer information to get access to other VM's on the same host.

19 questions
4
votes
2 answers

If Spectre and Meltdown OS patches are not applied on a Windows system, can other new Microsoft patches be applied?

In this Information Security QA, we thoughtfully discuss whether or not patching for Spectre and Meltdown are necessary on Windows boxes. Some will undoubtedly decide they want to patch certain Windows boxes, while others will decide they don't want…
Amazon Dies In Darkness
  • 9,990
2
votes
3 answers

Do Spectre&Meltdown microcode updates slow down the computer?

I have a question about Meltdown and Spectre. As far as I understood, the Windows patches are just workarounds and what really needs to be done are microcode updates Microsoft says that the computers will get slower due to the windows patch. My…
Daniel Marschall
  • 367
1
vote
0 answers

What versions of Windows use the PCID feature to speed up Meltdown patch?

I have Windows 7 Enterprise SP1 64 bit with an Intel i7-6820HQ (with latest microcode rev 0xC6) and InSpectre #8 says I have both protections, but SLOWER. Is it because Windows 7 does not use the PCID feature? Which versions do use it? Pictures: PS…
David Balažic
  • 1,970
1
vote
1 answer

What to do with a i5-5200U CPU running Win 8.1 in regards to Spectre and Meltdown?

I have a Lenovo g50-80 with an Intel i5-5200U CPU running Windows 8.1 64bits with all updates installed and no new updates available (only 2 optional ones that are irrelevant here). I just ran InSpectre and I am not protected whatsoever! :-( I'd…
ASR
  • 11
1
vote
0 answers

Spectre/Meltdown- Lenovo M800 BIOS update does not appear to work

So I've got a Lenovo ThinkCentre M800, running Windows 10 x64, 1709. I've applied their latest BIOS Update which is version FWKT86A, and then ran Get-SpeculationControlSettings (From the Speculation Control PS module which determines if your PC is…
ztnd13
  • 121
1
vote
1 answer

My BIOS is outdated. Will I be affected by Meltdown and Spectre?

I had made the mistake of buying a Lenovo Laptop. The model is Lenovo Flex 2-14. This laptop has a bios from 2014 and Lenovo never issued an update. I've been reading on some major sites that BIOS must also be up to date to prevent the latest…
Sameer M
  • 11
1
vote
1 answer

Computer won't boot - related to KB4056892 (Meltdown) update?

My computer has been doing strange and random things for the last year and I think it may have with a hardware problem I cannot find. However, on this occasion suddenly my computer wouldn't boot: after the BIOS I would get a black window with a…
user1314836
  • 398
1
vote
0 answers

What should I do about Meltdown and Spectre vulnerabilities with my Linux system?

I have GNU/Linux running on an (obviously recent enough) Intel CPU. I've heard about the grave security flaws which have surfaced, Spectre and Meltdown, although I haven't read the details yet. I've read there's been work done to patch kernels and…
einpoklum
  • 10,666
0
votes
1 answer

Analyze Spectre and Meltdown Check Script by Red Hat

As you know Red Hat published a script to check the vulnerability of the system to Spectre and Meltdown. Kernel upgrade and activation/deactivation of some features is enough for avoid from these vulnerabilities. But there is something in the result…
Jo Shepherd
  • 835
0
votes
1 answer

Meltdown and Spectre: practical advantages and disadvantages for users? (security and performances)

I was guessing which could be the practical downsides of the patches for these risks and also if a user decides to not apply these patches. Preamble: In the middle of January I bought a refurbished HP laptop, provided with an Intel i5-3320M (Ivy…
Giova84
  • 43
0
votes
0 answers

Post-Meltdown Patch Disk Performance

I am doing a school project regarding the Meltdown patches and how it affects performance, and was doing some disk benchmarks (CrystalDiskMark). Current setup is i5-8600K + Samsung 860Evo 250GB, and to my surprise, the Meltdown patch increased…
선풍기
  • 101
  • 1
0
votes
2 answers

Internet Explorer Inoperable after Meltdown/Spectre Patches in Windows 10

This started happening shortly after Meltdown/Spectre was in the news. I've tried: Uninstalling and reinstalling IE. Resetting IE settings Uninstalling KB4056892. Searching yields results for AMD processor PCs having boot problems, but I'm on an…
Dzejms
  • 123
0
votes
1 answer

Is KB4056759 part of Meltdown and spectre update fix?

I can't tell if it is part of Meltdown and Spectre. MS site says its a fix for "An elevation of privilege vulnerability exists in the Microsoft Server Message Block (SMB)". But a couple of sites link this update as if its part of it. Here is a link…
user
  • 3
0
votes
0 answers

Linux Server reboots unreasonably

After applying Meltdown and Specter fix for Linux my openSUSE Leap 42.3 server began to reboot unreasonably. It can work 1 day and then reboot or it can work for 15 mins after the last restart and then reboot again. This is the list of…
alexanoid
  • 175
0
votes
0 answers

how to update godaddy Dedicated linux server centos 6.9 kernel

I have dedicated server from godaddy. The Linux information is as follows. Version: CentOS release 6.9 (Final) Kernel: 2.6.32-042stab111.11 I have executed "yum update" on server and now /boot shows the following files. -rw-r--r-- 1 root root …
Suyash Jain
  • 294
1
2