> Final update: A couple of days before the embargo ended (and after I wrote the majority of this blog post), AMD told me what their patch for this vulnerability is [...] Although it is true that they now fully use HTTPS, the claim about signature verification is untrue; they only perform a CRC-32 check on the downloaded executable, which is not cryptographically secure.
It's ridiculous to consider MITM attacks out of scope for taking over your computer. Also, there are probably ways to exploit this without a true MITM like DNS cache poisoning. But it's best to just assume the whole internet is MITMed.
Various domain registrars have been compromised over and over again (often by children!), resulting in companies like Tesla and Cloudflare getting owned.
The reality is that any vaguely competent attacker can compromise a court clerk and just compel e.g. the .com registry to hand over whatever domain they want.
Although I suppose the aforementioned problem has significant implications beyond dns…
Out of scope does not necessarily mean out of impact. It is merely a question of how far a company wants to be responsible for the environment their software is run in. Most of the time that answer is "not much."
AMD's inability to make good software has been a recurring problem for decades. Many years ago I had some success with their optimising compiler, but everything else I've touched was bad. A real pity.
It's technically possible (though I don't know if they actually do this) that they're not referring to a signature check in the download part, but are verifying the code signing signature of the executable downloaded. You'd only notice the CRC if you were looking at the downloaded content, but if the updater refuses to launch an executable that isn't signed by AMD's cert then they would be fine.
Given the way AMD has been treating this issue, I'm assuming they're just incompetent, though.
Especially because if they had read about or studied this problem they would find tons of prior art where CRC32 was considered not secure for solving the problem. CRC32 solves a different problem -- how do you verify that the data that was received is identical to the data that was sent. It makes no guarantees about who is sending the data, which is the real problem signatures solve.
More specifically, it solves the problem of verifying that the data received was not accidentally corrupted somehow. Unlike cryptographic hashes, CRC32 does not do much to defend against deliberate, malicious modification. It's too easy to craft some different data that matches a given CRC32 value.
Computing a CRC is equivalent to attacking it. The checksum is the value that produces a certain fixed constant when appended to the data. This is why you'll often see checksums as the last field in a message. It allows for hardware to verify the entire message by checking if the CRC of the bytes equals that fixed constant without having to parse it.
There's two requests involved for the auto updater, one to grab the XML file, and one to grab the driver file over plain http.
If the autoupdater can't handle the redirection when grabbing the XML file, then it's a case of accidental safety by mistake that would prevent grabbing the plain http file.
AMD's utter incompetence when it comes to the software side of things is truly, truly baffling to me. It's not like you need a mountain of developers, a team or two on the right project would do wonders for their market share.
For example: Implement the CUDA. CUDA's won, hands down, that toothpaste is solidly outside the tube. Luckily, to the outside observer CUDA is just an API, and API's aren't copyrightable. Literally nothing is stopping AMD from hiring a relatively small team of developers to make AMD GPUs CUDA-compatible.
I think we can all agree that MiTM is a valid attack vector and this should have paid out the bounty. AMD won't do it, but perhaps we can crowdsource it - the dude deserves it. Join me in doing this: https://ko-fi.com/mrbruhh (identical link to the one in the write up, feel free to verify).
I am a diehard fanboy of their GPUs, and have been since they were still ATI but I had to finally purchase an nvidia GPU because of how bad AMDs software quality is.
My powerful 5700XT spent two years basically broken, because the default, driver provided fan curve locked the fan at 27%. For two years, I couldn't figure out why my GPU constantly crashed, because it was overheating, because the default fan curve prevented the GPU from keeping itself cool and it would eventually just give up.
That diagnoses was complicated by the fact that AMD GPUs just resetting is very common. There's a watchdog timer in Windows that resets parts of the GPU stack because Microsoft is traumatized by 60% of Windows Vista BSODs being caused by bad nvidia drivers. Apparently sometimes if you increase this watchdog timer, the GPU eventually finishes whatever was giving it trouble.
But I still love AMD, and the ryzen line is a great value in the mid range. So I bought another AMD CPU and am very happy with it. But it somehow included software and this specific auto updater utility. Which I don't need, since I don't want to update the drivers for a GPU that I shouldn't be using (maybe except some video encoding lift, but my GPU can do that too). But I could not figure out a way to kill or prevent this stupid little autoupdater utility which always steals focus, for no reason at all. It shouldn't even be popping up a CLI! Windows task scheduling is incredible and would do this without a problem, and give you all the infrastructure to notice this was happening!
Drivers got better after ATI merged/got bought by AMD, but ATI has a loooooong legacy of terrible drivers in Windows.
The funny thing is, in Linux, the drivers are pretty great as far as I can tell. It's not like there aren't bugs, probably, but mostly everything "just works". You can't depend on FSR in Linux, for example - Doom Eternal just goes blank if you turn it on. I can live without it, though, and everything else seems fine, including performance.
Nvidia linux drivers make me quite upset - they're fine once you finally get them working, but you approach Nvidia driver updates with extreme caution in Linux
MITM because you used http instead of https and you don't have any other verified cryptographic signature on your data -- get tae fuck, fix it pronto.
Various domain registrars have been compromised over and over again (often by children!), resulting in companies like Tesla and Cloudflare getting owned.
The reality is that any vaguely competent attacker can compromise a court clerk and just compel e.g. the .com registry to hand over whatever domain they want.
Although I suppose the aforementioned problem has significant implications beyond dns…
Same reason security programs exclude social engineering, even though that's a pretty common way for companies to get pwned.
Given the way AMD has been treating this issue, I'm assuming they're just incompetent, though.
That’s my take.
Love this. I am frustrated by idiot software features everywhere, but am not triggered yet to punish them. AI automation is coming close however.
Works great!
If the autoupdater can't handle the redirection when grabbing the XML file, then it's a case of accidental safety by mistake that would prevent grabbing the plain http file.
For example: Implement the CUDA. CUDA's won, hands down, that toothpaste is solidly outside the tube. Luckily, to the outside observer CUDA is just an API, and API's aren't copyrightable. Literally nothing is stopping AMD from hiring a relatively small team of developers to make AMD GPUs CUDA-compatible.
Don't bother to use Windows?
I started it with $100 - https://ko-fi.com/transactions/03df753c-09b0-4972-8e53-adf06...
I am a diehard fanboy of their GPUs, and have been since they were still ATI but I had to finally purchase an nvidia GPU because of how bad AMDs software quality is.
My powerful 5700XT spent two years basically broken, because the default, driver provided fan curve locked the fan at 27%. For two years, I couldn't figure out why my GPU constantly crashed, because it was overheating, because the default fan curve prevented the GPU from keeping itself cool and it would eventually just give up.
That diagnoses was complicated by the fact that AMD GPUs just resetting is very common. There's a watchdog timer in Windows that resets parts of the GPU stack because Microsoft is traumatized by 60% of Windows Vista BSODs being caused by bad nvidia drivers. Apparently sometimes if you increase this watchdog timer, the GPU eventually finishes whatever was giving it trouble.
But I still love AMD, and the ryzen line is a great value in the mid range. So I bought another AMD CPU and am very happy with it. But it somehow included software and this specific auto updater utility. Which I don't need, since I don't want to update the drivers for a GPU that I shouldn't be using (maybe except some video encoding lift, but my GPU can do that too). But I could not figure out a way to kill or prevent this stupid little autoupdater utility which always steals focus, for no reason at all. It shouldn't even be popping up a CLI! Windows task scheduling is incredible and would do this without a problem, and give you all the infrastructure to notice this was happening!
The funny thing is, in Linux, the drivers are pretty great as far as I can tell. It's not like there aren't bugs, probably, but mostly everything "just works". You can't depend on FSR in Linux, for example - Doom Eternal just goes blank if you turn it on. I can live without it, though, and everything else seems fine, including performance.
Nvidia linux drivers make me quite upset - they're fine once you finally get them working, but you approach Nvidia driver updates with extreme caution in Linux