Any way to hide CPU info from Whonix?

[helpmeplzz]

Hello. Usage of Whonix does hide the GPU name but doesn’t hide the CPU name and vendor. Is it possible to hide hardware from Whonix in order to make it more secure and decrease fingerprinting?

[HulaHoop]

Yeah you can run it under QEMU full emulation mode if you can put up with the slow perf. No official support however:

QEMU

[Patrick]

security-misc: Enhance Miscellaneous Security Settings

[helpmeplzz]

Thanks, I will try it. But in practice, can destination website see the hardware information using remote JavaScript code or hardware info leak is only possible when Whonix Workstation is compromised?

[Patrick]

Prerequisite reading, partially already answered on same link security-misc: Enhance Miscellaneous Security Settings.

CPUID is a mess and I don’t think there is any method to curb it.

CPUID

Then then I found this cpuid x86 in JavaScript. but didn’t look into further.

Speculation: even if using security-misc: Enhance Miscellaneous Security Settings (or maybe even QEMU) it might still be possible to benchmark the browser to guess what hardware is being used and/or to fingerprint the browser. Using JavaScript. Or perhaps even without. For Tor Browser specific questions, I recommend, there is likely better information from Tor Project as per Free Support for Whonix ™.

[Patrick]

Related:

Protocol Leak and Fingerprinting Protection ‎

[HulaHoop]

@helpmeplzz

But in practice, can destination website see the hardware information using remote JavaScript code

They can perhaps get some idea by benchmarking your CPU with JS.

[anonymousman]

@HulaHoop

They can perhaps get some idea by benchmarking your CPU with JS.

Is it worth to try to hide CPU info from applications inside Workstation? There might be a paradox: enabling hide-hardware-info.service can make you ‘a unique guy who uses hide hardware info’. Or not?

It is better not to hide CPU info but set up the most common CPU vendor and model in my opinion.

[HulaHoop]

@anonymousman

Is it worth to try to hide CPU info from applications inside Workstation?

The less identifying info the better, if possible.

@anonymousman

There might be a paradox: enabling hide-hardware-info.service can make you ‘a unique guy who uses hide hardware info’. Or not?

If there is a large userbase running it then it will end the paradox and provide safety in numbers.

@anonymousman

It is better not to hide CPU info but set up the most common CPU vendor and model in my opinion.

Short of running a purely emulated CPU , there will be ways to benchmark and identify the hardware.

[Patrick]

Further discussion on CPUID happened here:

Restrict Hardware Information to Root - Testers Wanted!

Please test so perhaps this feature can be enabled by default. Details about your hardware can be used for identification, so Whonix includes the hide-hardware-info.service systemd unit that restricts access to /proc/cpuinfo , /proc/bus , /proc/scsi and /sys to the root user only. This hides most hardware identifiers and increases security as /sys exposes a lot of information that should not be accessible by unprivileged users. This setting is disabled by default because it might break many a…

[Waltz5]

If you’re currently using Whonix for KVM and you’re using Virt-Manager, you can go to CPUs, disable host-passthrough and select qemu64.

If you prefer editing the XML:

<cpu mode="custom" match="exact" check="none">
  <model fallback="forbid">qemu64</model>
  <feature policy="require" name="ibpb"/>
  <feature policy="require" name="md-clear"/>
  <feature policy="require" name="spec-ctrl"/>
  <feature policy="require" name="ssbd"/>
</cpu>

To be sure it worked check by running cpuid inside Whonix-Workstation before and after changing it. Your CPU model name should be QEMU Virtual CPU version 2.5+ after the change.

However, this could introduce vulnerabilities or attack surface, as it has not been researched yet, as mentioned below by Patrick.

[Patrick]

@Waltz5

If you’re currently using Whonix for KVM and you’re using Virt-Manager, you can go to CPUs, disable host-passthrough and select qemu64.

This was discussed here:

Potential improvements for Virtual Machine Cloaking - KVM

By default, the CPU model information is leaked, which significantly reduces anonymity when running untrusted software. This issue can be addressed (with a slight performance impact) by using KVM and changing the CPU model to ‘qemu64’ instead of ‘host-passthrough’. Additionally, ensure that necessary features to protect against Spectre, Meltdown, and other attacks are enabled. <cpu mode="custom" match="exact" check="none"> <model fallback="forbid">qemu64</model> <feature policy="require" na…

Not safe without further research, pending todo tasks:

Potential improvements for Virtual Machine Cloaking - KVM

We might be able to change the default configuration files but maintaining a different set of configuration files is unfortunately unrealistic due to lack of KVM contributor activity. This should be sufficient on Intel processors to protect against Spectre and Meltdown attacks. Since nobody else on the internet claims to do that, and this being highly complex question with security impact… TODO: Contact Qemu-discuss Info Page and ask if this is secure or vulnerable to any CPU hardware s…

[VulkanWarmaster3K]

Very interesting info information I plan to look into this more.

Virtualbox is a type 2 hypervisor as compared to KVM which is a type 1 and imo in provides better protection but downside is it’s not user friendly compaired to Virtualbox though but thats off topic.