Mystery Microsoft bug leaker keeps the zero-days coming
theregister.com
theregister.com
so it gives you access to an encrypted volume which automatically unlocks anyway
the only difference is that it immediately gives you root access to the volume instead of having to go through the Windows login procedure - this might be a stolen laptop you dont have an account on
> Second thing is, No, TPM+PIN does not help, the issue is still exploitable regardless, I asked myself this question, can it still work in a TPM+PIN environment ? Yes it does, I'm just not publishing the PoC, I think what's out there is already bad enough.
https://deadeclipse666.blogspot.com/2026/05/were-doing-silen...
If you use bitlocker in the default, insecure way, where the TPM is configured to hand the decryption keys over to the enrolled Windows environment automatically, you can just get an LPE to access the running Windows environment after it boots. That's what I think the published exploit does. It really isn't even related to bitlocker itself, right?
AIUI, TPM+PIN should actually mean the TPM itself cannot release the keys because the PIN hash is actually part of the key material.
So what would a TPM+PIN exploit even look like?
Or if you have physical access, you can probe the TPM chip with a SPI decoder to get the key directly: https://post-cyberlabs.github.io/Offensive-security-publicat...
Another method is via PXE (still not patched on most systems apparently): https://github.com/andigandhi/bitpixie
> TPM+PIN should actually mean the TPM itself cannot release the keys
It does release the (wrapped) key actually (the above cyberlabs link explains it), it's just that the KP data this time has additional layers of encryption that are based on the PIN, which is decrypted in software after the fact. This means you can crack it offline. With the default minimum of 6 digits you can probably bruteforce it within a day.
If you're paranoid I might suggest switching to a full password-based pre-boot auth option instead of the PIN.
> BitLocker hashes the user-specified personal identification number (PIN) by using SHA-256, and the first 160 bits of the hash are used as authorization data sent to the TPM to seal the volume master key.
So what's actually happening is that the PIN is used to derive an authValue passed to the TPM, which compares it to the expected value, and can trigger lockout on too many mismatches.
I can't find specifics to how Windows configures the TPM wrt. lockout, but the mechanism described in the article appeared fishy to me, and contradicts official docs. It also would not make sense that TPM+PIN was known to be safe against bus sniffing attacks if it would still reveal all data required to brute-force the PIN.
[1] https://learn.microsoft.com/en-us/windows/security/operating...
https://blog.scrt.ch/2024/10/28/privilege-escalation-through...
This one does say "it appears that the user’s PIN is sent to the TPM which releases the intermediate key only if the provided secret is correct, thus effectively preventing offline bruteforce attacks."
Given this, I can't see how it would be possible for anything like YellowKey to work on a cold booted TPM+PIN system without someone already knowing the PIN.
Perhaps when the exploit author said "it works with PIN" they meant "it works if you enter the correct PIN"... or they are just lying. I'm not sure.
So this person's claim to have a TPM+PIN attack might imply they are able to use the same LPE to get a (PIN-encrypted) key from the TPM then they can simply brute force?
I also disagree that the PIN bypass would be "10 times more impressive," but that's just my professional opinion.
https://post-cyberlabs.github.io/Offensive-security-publicat...
I don't think that's true. Some vendors have a better track record than others. Nobody's popped the storage encryption on iOS or MacOS devices yet AFAIK; and the fact that it's tied to a hardware secure element makes it pretty strong.
There's levels of trust/security.
I generally trust Apple's device encryption, assume BitLocker can be popped by a well-equipped nation state attacker, and the rest I trust about as far as I can throw them.
PS: A related issue was (is?) that the comms between the CPU and the TPM chip on the motherboard isn't encrypted, signed, or in any significant way protected! Apparently it's relatively trivial to extract various keys including BitLocker encryption keys by simply clipping an oscilloscope to the TPM chip pins.
Reference: https://www.techcentral.ie/windows-bitlocker-no-longer-trust...
That's just the default OPAL key.
The idea was that you are supposed to SET the key... they made all paths go through the encryptor, so "unencrypted" was just a key with zeroes.
Ah, yes. Wave EMBASSY Suite, Wave Preboot, and all that other hot garbage.
Best part of Wave Systems was their horrid support organization. I loved being the tier 0 rep they contracted and trained with zero software knowledge and being a catch-and-throw for all the angry people that locked themselves out of their laptops. "Sorry, buddy, all I can do is make you a Dynamics CRM ticket."
Care to share a quote?
There is no way for us, the users, to know wherever they have the capability to add additional keys to decrypt the data because the platform isn't open source and doesn't have attestation wrt what's actually serving the requests.
And it's worth remembering that apple had similar articles published before prism too which were ultimately proven to be groundless by prism.
There needs to be trust at some level, and trust in Apple the entity to not be outright lying about its thoroughly documented security posture is a reasonable level of trust for most people on the planet, including those who are at very real risk of targeted attack by state-level actors.
Thank god this is not the world where things get hacked all the time and where any claim of meaningful security is a extraordinary claim that demands extraordinary evidence and proof before credibly asserting it, but everybody just ignores that part and just pinky promises it and everybody just believes them for the 104th time without evidence.
There doesn't seem to be any other plausible explanation. The reckoning needs to come and people need to stop using their products for good.
Would love a whistleblower to explain which part of the government or company forced it.
In some ways the hysteria of sorts is peculiar....its not like we never had secure cybersecurity either its just that we have too much on the cloud and institutions of trust without questioning it because of herd behavior and empty suits.
Like the timing of all of these seemingly disparate events from "mystery lonewolf" is too obvious and I'm not the one to entertain conspiracies either.
CachyOS is pretty amazing, too.
I mean, there is some in the high assurance space, but that has never trickled into the broader consumer sphere. Are you referencing those systems? I am unaware of anything else.
the same one who takes care of Cisco ? and Google ? and ...
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One more reason to stick with open source, auditable solutions. Any backdoor in open source software would be quickly noticed by the community (such as recently when NPM packages got compromised).
This year looks very refreshing for software. My guess is because of the AI-assitance in grinding an unlimited amount of code. While I feel sorry for maintainers and developers who have a new CVE everyday, society seems to be sweeping away 20 years of backdoor development by shady companies and spies, making computing actually safe and trusted for the first time in our lifetime.
Or not laid off at all, but otherwise disgruntled security researcher who prompted AI to concoct some personal details that seem to be in line with someone inexplicably dropping Microsoft zero-days.
YellowKey Bitlocker Bypass Vulnerability