The BitLocker exploit seems simple and very dangerous. Companies and individuals have been relying on BitLocker to protect information if the device is lost. Despite promises, Microsoft doesn’t seem to be serious about security.
What will it take for more companies to truly understand their risks with Windows and being locked into Microsoft’s platforms?
It seems undeniably a backdoor, why on earth would a very specific folder/file name and a specific boot combination just "magically" open up an encrypted drive.
It also doesn't help this comes from a person who likely was close to the development at Microsoft (one way or another) as their recent disclosures are quite alarming.
Of course, this could technically be the stars aligning type bug, but it seems like a purposefully planted backdoor to me.
This looking so much like an intentional backdoor just makes me wonder even more about TrueCrypt's sudden recommendation in 2014 that everyone switch to BitLocker. This particular backdoor didn't exist then (it's only Win11 apparently) but this sure makes it seem more plausible that another one might have.
Though if TrueCrypt was killed to try and get people to switch to encryption that could be backdoored, then why allow its successor VeraCrypt to exist? It's open source and independently audited, so it really shouldn't be backdoored.
It's not an actual backdoor. An attacker found a way to exploit Windows after booting it up in this recovery mode. The security of files on the device depends on it being impossible for Windows to be pwned by an attacker on any surface exposed before the user is unlocked.
This is why operating systems like GrapheneOS disable the USB port on the initial boot to limit the attack surface that an attacker has.
What would you require to feel confident it is a backdoor?
Nadella gives a press release, "Alright guys, you got us fair and square. Backdoor on Bootlocker. Various versions of it for years on behalf of the spooks."
You are unlikely to ever get a confirmation of wrong doing. That being said, for a first line security posture, there is no way external media should have anything to do with the encryption process. Even if the OS chose to read a USB drive, to also delete the magical files is ridiculously suspect.
How is this even possible, backdoor or no? Isn't the whole point of this type of encryption that even a compromised machine can't decrypt without the passphrase? If this works it means that the key is stored unencrypted somewhere?
For those who use password (not PIN) based pre-boot authentication with BitLocker... do we know if that setup is safe?
I can't imagine there would be a way to bypass that if a password is required, unless it was a situation where like, there was originally some secret secondary key made that needs no password... or the password was never tied to the key in the first place.
https://infosec.exchange/@wdormann/116565129854382214
> Mitigation: Use Bitlocker with a PIN.
> (Note: The YellowKey author disagrees that PIN is a protection
Here's the primary source: https://deadeclipse666.blogspot.com/2026/05/two-more-public-...
Other links:
https://github.com/Nightmare-Eclipse/YellowKey
https://github.com/Nightmare-Eclipse/GreenPlasma
What's with all the new accounts on these threads downplaying this? Why is it only the brand new accounts? What's going on here?
I've seen every variant of:
1) "this is an authentication bypass not a bitlocker bypass" (? what are you even trying to say)
2) "even though the attacker explicitly claims this bypasses TPM+PIN, that isn't actually true or what he meant"
3) "we shouldn't jump to conclusions that this is a backdoor"
The BitLocker exploit seems simple and very dangerous. Companies and individuals have been relying on BitLocker to protect information if the device is lost. Despite promises, Microsoft doesn’t seem to be serious about security.
What will it take for more companies to truly understand their risks with Windows and being locked into Microsoft’s platforms?
How does a bug equate to "not serious about security"?
There's no way this is not a backdoor
Read the article. It’s pretty clear that this is a backdoor, and calling it a bug would be so generous as to be misleading.
It seems undeniably a backdoor, why on earth would a very specific folder/file name and a specific boot combination just "magically" open up an encrypted drive.
It also doesn't help this comes from a person who likely was close to the development at Microsoft (one way or another) as their recent disclosures are quite alarming.
Of course, this could technically be the stars aligning type bug, but it seems like a purposefully planted backdoor to me.
*in your opinion.
The blog author calls it that but given there’s no root cause yet it’s foolish to jump to conclusions.
This looking so much like an intentional backdoor just makes me wonder even more about TrueCrypt's sudden recommendation in 2014 that everyone switch to BitLocker. This particular backdoor didn't exist then (it's only Win11 apparently) but this sure makes it seem more plausible that another one might have.
Though if TrueCrypt was killed to try and get people to switch to encryption that could be backdoored, then why allow its successor VeraCrypt to exist? It's open source and independently audited, so it really shouldn't be backdoored.
Funny you should say that... https://news.ycombinator.com/item?id=47690977
Remarkable. Does MS take a huge reputational hit for having a backdoor, or are they so essential to most places this won’t matter?
I’m assuming the EU speeds up the uncoupling cause of some of this.
It's not an actual backdoor. An attacker found a way to exploit Windows after booting it up in this recovery mode. The security of files on the device depends on it being impossible for Windows to be pwned by an attacker on any surface exposed before the user is unlocked.
This is why operating systems like GrapheneOS disable the USB port on the initial boot to limit the attack surface that an attacker has.
As far as I can tell, there's no concrete evidence that it is actually an intentional "backdoor."
What would you require to feel confident it is a backdoor?
Nadella gives a press release, "Alright guys, you got us fair and square. Backdoor on Bootlocker. Various versions of it for years on behalf of the spooks."
You are unlikely to ever get a confirmation of wrong doing. That being said, for a first line security posture, there is no way external media should have anything to do with the encryption process. Even if the OS chose to read a USB drive, to also delete the magical files is ridiculously suspect.
lol it’s an obvious backdoor. No way a security system would ever allow this blatant workaround to bypass all encryption. Backdoor is the only answer
> lol it's an obvious backdoor
in your opinion
Earlier thread: https://news.ycombinator.com/item?id=48114997
How is this even possible, backdoor or no? Isn't the whole point of this type of encryption that even a compromised machine can't decrypt without the passphrase? If this works it means that the key is stored unencrypted somewhere?
Most setups only have the key stored in the TPM, so all you need to get it back is a signed/trusted bootloader.
Ideally you'd want that key to be further protected with a password or some other mechanism because it's not impossible to extract TPM keys.
Presumably the key is stored in the TPM
[dupe] https://news.ycombinator.com/item?id=48129789
And earlier
https://news.ycombinator.com/item?id=48114997
For those who use password (not PIN) based pre-boot authentication with BitLocker... do we know if that setup is safe?
I can't imagine there would be a way to bypass that if a password is required, unless it was a situation where like, there was originally some secret secondary key made that needs no password... or the password was never tied to the key in the first place.
The exploit developer themselves say [1] TPM+PIN is vulnerable, though no public PoC.
[1]: https://deadeclipse666.blogspot.com/2026/05/were-doing-silen...
I’m skeptical of that claim. The key material presumably is inaccessible even to the OS without the passcode.
> presumably
That's the thing, we don't actually know how involved the PIN is in relation to the key... it might be completely separate (and hence bypassable).
Similarly I also wonder if password-based pre-boot auth is affected.