So I got Fairphone 4, with /e/ os, a couple of days ago. When I connected it to my NextDNS I saw that it was trying to connect to some weird addresses, like every 5-10 minutes. I searched Internet a bit and found out that it was something with snapdragon cpu and location services. I travel a lot and use Organic Maps for navigation, so location was enabled almost all day on the phone. I turned off location services and connections stopped, and everything was fine for a couple of days.
Today I came home, checked logs in NextDNS and saw that phone started doing the same connections almost constantly even with location turned off.
Can I do something about this, other than allowing these connections? These connections are probably so numerous because they are getting blocked. If I allowed them, phone would maybe call home once in a couple of hours. I would rather not allow them, but I don’t want 20% of battery to be eaten by this.
The TPM can’t do anything. The Intel Management Engine and AMD Platform Security Processor can, but the TPM is just key storage.
That stuff is disabled unless you buy expensive business options, though. Intel makes a lot of money not putting the fancy smart stuff into their desktop platforms.
For remote wipe you also need to get lucky because if the thief doesn’t install the necessary drivers. Enabled encryption should prevent your company’s data from falling into the wrong hands, of course.
I think unless the HAP bit is specifically set to 1, Intel ME is still active on consumer boards, just without an interface for the OS to interact with it. Not sure if someone has hacked an OEM UEFI/BIOS to interact with it, but I have seen a different MAC address from my PC on my network before, and this is without any virtual adapters. This is the only explanation I can come up with.
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Thanks for your comment, much appreciated! Could you provide a source for someone who has reverse-engineered a recent version of ME and has found not much incriminating behaviour for consumer motherboards?
Unfortunately,
me_cleanerdoesn’t seem to work too well with newer chips. Fortunately for me, I’m planning to purchase older computers, but for people who aren’t, this doesn’t help much (as far as I can see).Thank you for the idea of extracting the BIOS to enable the HAP bit. Won’t it require some serious reverse-engineering chops to find the HAP bit and enable it inside of such a binary blob? I’m not really used to Ghidra yet haha.
If I remember correctly, ME uses its own MAC address, but the same IP address of the host. Or maybe this is no longer the case. How would it extract packets though? Won’t that require serious compute power? Or does it look for packets with specific labels identifying them?
Thanks for letting me know about MEinfoWIN. I’ll try and find it!
It’s hard to prove a negative, but with people doing deep dives like these not finding any malicious behaviour yet, I doubt there’s anything of note happening in the ME on consumer hardware.
Theoretically the NSA could backdoor the IME, but if they can backdoor the ME firmware, they can also backdoor the tiny Pentium processor inside every Intel CPU, or the UEFI ROM, the microcode, or any other firmware really. In practice they plant tiny their own chips onto existing motherboards, which can be easily removed so they don’t leave a trace.
It looks like the HAP bit has changed location (someone already found out the new offset) but me_cleaner has built in support for setting the bit in many cases; this commit from this PR seems to implement that. Disabling the firmware does, as you would expect, disable the firmware loading process though, meaning Intel Audio won’t work right and booting becomes weirdly slow. You also lose fTPM support and modern sleep (S0ix).
The packets enter the Intel network card, and the network card pre-processes them in a bunch of ways (validating checksums, sometimes even reassembling fragmented frames). Modern network cards are fully aware of IP and in limited fashion TCP, so “extract traffic towards port 664/16993/16995 and do not notify the OS” isn’t that hard to accomplish.
A separate MAC with the same IP would cause tons of conflicts on the network, I don’t think Intel would (intentionally) use that approach.
Thank you, that clears it up. I’m not as informed on this matter as I used to be in the past, apologies for any assumptions I might have made.
Thanks for the link and the link to the PR, I might try this with a PC or two in time. Do I need Intel Audio for Pipewire to work? I didn’t quite grasp the ramifications of certain parts of the firmware not working such as Audio and Sleep; would I need to find a software solution for Sleep? Also, will this affect C-states by any chance?
That makes a lot of sense. Maybe I was looking at something different in my network at that point. Thanks again!
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Thanks. I was planning to use a USB connection to a DAC for audio, but I’d like to be able to use the speakers on my monitor too, if possible. I’ll be using a desktop computer.
Here is an alternative Piped link(s):
deep dives like these
Piped is a privacy-respecting open-source alternative frontend to YouTube.
I’m open-source; check me out at GitHub.
For what it’s worth, I did specifically say ecosystem because the TPM is just one component, which is required to authenticate the remote wipe. Also the drivers are installed automatically with most modern operating systems, it’s not like you install your own south bridge driver, for example. Linux of course notwithstanding.
I’ve seen it used successfully numerous times. Someone steals one of our laptops, rips the drive out, installs vanilla windows, and boom it reboots and performs a wipe.
Regardless, system-on-a-chip are just that, systems; they can absolutely make remote calls without user interaction, just as intimated by the comment you originally replied to.
Ah, in that case I suspect this has less to do with the TPM or firmware and more with a weird feature Microsoft provides (that I permanently turned off on my laptop).
Windows provides the option for the BIOS to place or replace files on the file system. A bunch of anti-theft tools replace chkdsk.exe, which gets executed on every boot, with a daemon or installer for their service. You can clean install Windows all you want, the moment Windows boots, injection takes place and the payload gets executed. You don’t need TPMs or even encryption or Intel ME/AMD PSP for this.
I believe MS added this API because they noticed motherboard manufacturers messing with the kernel’s memory, and decided to expose a less batshit insane API rather than risk customers blaming Windows for their laptops crashing on boot because the memory layout changed.