Seems this traces back almost a week, from Nightmare-Eclipse who is the researcher who found this:
Tuesday, 12 May 2026 - "Here are the links, yes, two vulnerabilities this time [YellowKey] [GreenPlasma] [...] Next patch tuesday will have a big surprise for you Microsoft"
Wednesday, 13 May 2026 - "I can't wait when I will be allowed to disclose the full story, I think people will find my crashout very reasonable and it definitely won't be a good look for Microsoft."
First post in March 2026 is "[...] someone violated our agreement and left me homeless with nothing. They knew this will happen and they still stabbed me in the back anyways, this is their decision not mine."
I'm not sure what to make of it, is this someone essentially "leaking" things from the inside? Sure sounds like it, and others are able to reproduce the results.
I read it as the author is / was going through the vulnerability disclosure process with Microsoft and they're annoyed for unclear reasons and decided to publicly disclose, rather than being an insider.
Many brilliant people have serious mental health issues that preclude their ability to regulate their emotions and act maturely in serious situations e.g. responsible vulnerability disclosure.
I've watched genius-level IQ people get fired time and again because they don't know how to work with others at a basic kindergarten level.
To be honest if I got fired in a mean or unfair way I'd definitely hit back at my employer in such a manner if I'd have the ability to. I'm unlikely to have that though as I'm not aware of any saucy company secrets. But if this is what happened I think it's pretty justified.
The secret here seems to be that Microsoft caches the key somewhere even when it's supposed to be only in the TPM! That's a pretty big revelation IMO.
> The secret here seems to be that Microsoft caches the key somewhere even when it's supposed to be only in the TPM!
Not what happened here (I reserve my judgment wrt the promised TPM+PIN exploit).
In the default TPM-only mode of BitLocker, the secret is in fact in the TPM, which will (as instructed by Windows upon key creation) release it to the correct OS running on the correct computer. Notably not in the picture is any user-provided data: measured boot is the only protection. It is only the correct programming of the OS that makes it request an account password (completely unrelated to the disk-encryption cryptography) before letting the user poke at the disk, which the OS can at that point already decrypt.
Well, turns out the programming is such that if you ask politely it’ll just pop an Administrator(?) shell.
> Not what happened here (I reserve my judgment wrt the promised TPM+PIN exploit).
Yes this is the one I'm referring to.
I have noticed it myself, it has happened to me that my system rebooted to install updates and it did not pass through the blue TPM pin entry screen at that point. That was a big red flag for me. A normal reboot always does that, even a 'hot' reboot.
> BitLocker is now suspended, which means the drive remains encrypted, but Windows temporarily stores the unlock information so firmware changes won’t immediately trigger recovery.
> A normal reboot always [forces the TPM pin entry screen], even a 'hot' reboot.
In TPM-only mode, I only see the screen—which asks for an recovery key that serves an alternative to the TPM-borne secret, not for whatever you are calling the “TPM PIN” here—whenever I update the firmware or the bootloader (the latter from the other side of the dual-boot setup). Otherwise it boots straight to the login screen, which meshes with the measured-boot-only theory of operation I’ve described above. There’s nothing nefarious in this part, even if I think it exposes an unwisely large attack surface (e.g. the USB stack). I suspect you simply reboot so rarely you’re never hitting the happy path.
No I have the explicit PIN turned on. That means it requires a Pin entry on each boot. It's not the recovery screen though it looks similar. It's also not a password that's then hashed. It unlocks the TPM with a short pin, the number of attempts is limited by the TPM itself so that it doesn't get brute forced.
This is not a standard option, I think it can only be set through a group policy.
> To be honest if I got fired in a mean or unfair way I'd definitely hit back at my employer in such a manner if I'd have the ability to.
I knew a contractor that developed a habit of not paying his workers for a short time. After people started walking off job sites with his tools and showing up at his house demanding to get paid, he magically found the money to pay them.
It’s pretty unsurprising how vindictive regular people rapidly become when they’ve been ripped off.
Reporting wrongdoing to the ones doing it doesn't work. Perhaps they relied on Microsoft a bit too much for their livelihood and are just beginning to reevaluate their decisions. It's not so rare for brilliant people to live a life of the mind and not pay enough attention to their material conditions. But defining that as "serious mental health issues" is such a cheap shot.
> Reporting wrongdoing to the ones doing it doesn't work.
Most large companies — including Microsoft [1] — have an internal affairs call center where you can anonymously report issues of malfeasance — assuming that's what happened here.
Yeah I'm getting a lot of pressure to be a "team player" lately. I've told them over and over I'm not capable of that and that has never been a problem before. But we have a hipster new VP who is really pushy and wants to generalise everything.
"Not being a team player" doesn't mean the person is a nuisance, but they can be an introvert who has a limited interaction budget and can work silently and efficiently otherwise.
This generally means the person might not leave their cubicle much or give feedback frequent enough, but this doesn't mean they are not motivated to help others or share knowledge. One can approach and ask a question and get tons of help immediately.
How I know? That's me. I look like a cave dweller from a distance, but I'm not. The only difference I have is human interaction sometimes drains me a lot, so I just concentrate and work, yet everybody get their help immediately if they need them.
Also, no, I don't bite or belittle people. On the contrary.
Assuming the worst in others is bad. If I worked with you, I'd be looking for somewhere else the moment I found out how you think about me.
Remember. People don't leave bad jobs, but bad managers.
I have worked with lots of introverts and my empirical observation is that the introversion/extraversion axis is completely orthogonal to whether or not someone can be a team player.
You require both team players and "rockstar" individuals. It's not one or the other or a competition, because they do different things.
Yes if you put a someone who can't work on a team on a team and expect team work then that will not work. But that's obvious, so then don't do that. Expecting a homogeneous workforce isn't realistic or optimal.
I'm not a software engineer at all. And I tend to take on projects nobody else wants because they are too complicated or esoteric.
And I didn't say I'm not capable of being part of a team. Just that I need to have my own responsibilities within a team. I can't deal with micromanagement or excessive coordination like 'standups' every day.
Yeah you've completely misread this. The phrase "not being a team player" is a euphemism for someone not willing to do dubiously unethical or illegal (or things that go against internal company policy) things in support of a low level supervisor or manager's wishes. Or more favourably, someone who's unwilling to do things outside of what he's actually paid for or to do things unpaid (or outside working hours etc.). Also known as wage theft.
The guy saying that he has been accused of "not being a team player" isn't literally quoting his management here. He's summarizing that his immediate supervisors don't like him because he's unwilling to enter in some patronage like relationship with them.
The fact that you gave the benefit of the doubt to some faceless employer here instead of an actual person recounting his experiences is really sad and maybe ought to be reason for you to rethink your biases to jump to the conclusion that this guy is a toxic loner. Sounds like you're projecting hard here from some other experience.
That is also a thing yeah. It's not really unethical or illegal but our VP has a huge preference for snazzy glitzy projects and never wants to tackle the problems that cause real pain in the organisation because they are not spectacular and don't make him look good. And yes I bring that up whenever it comes into play. I'm definitely not an order-follower.
> I've told them over and over I'm not capable of that
I can relate and empathize. And also provide this suggestion based on my own similar experience: if you can't provide evidence (e.g. doctor's diagnosis) that you are "special" or "not capable of that", then they don't have to care and will take steps to force you out. I wish you all the best.
Here in Europe it's different, we have more rights. Unfortunately I don't have an official diagnosis but I'm definitely neurodivergent. I've been meaning to get one but it is difficult.
I was once (12 years ago) told: "they debate, they decide, we deliver" along with other "teamwork" pablum. This evil has been with us for a very long time, unfortunately.
Nonsense. there are way more accommodations for people who wouldn't have had a place 20 years ago... those accommodations have changed what a "standard IC" is. There never was a place for run-of-the-mill geniuses who couldn't be bothered to spend a few hours researching P2P (Person to Person) protocols. They were always pushed off to small companies where the risk was much lower. This hasn't, won't, and shouldn't change. If that makes you salty, I got some things I'd recommend you research.
Adults pay rent in money, not feelings. The answer to “how could Microsoft leave you homeless?” is “by not paying you”, not some bizarre “by making you feel so bad you lose your house, which you pay for with good feelings”
This is an oddly passive-aggressive comment when a much more likely read is they were relying on the funding and the large tech company did what large tech companies do and started moving slowly.
And I can see others already blaming them for relying on the vulnerability for living expenses, but if we can hold the hyper-rationalization for a second, we shouldn't be against the person who expected an organization with more money than God to uphold a deal for relative peanuts, right?
Like yes we all get that large orgs make spending $5 very hard, many claps for being the in-group, but their frustration would be understandable.
I'm supposed to feel bad that Microsoft didn't immediately wire him an advance on the bounty before validating anything? Have you ever tried to get anything corrected with a corporate payroll department? Try three months minimum.
It's like suggesting someone was relying on a lottery ticket to payout to survive.
I tried to be as coddling with my language as possible.
Acknowledged how orgs work, separated blaming the org from sympathizing with their reaction, tried to separate the prudence of their actions from the sticky situation they'd still be left in by the orgs actions...
But it was for naught: people are really ingrained in a weird "might-makes-right" model of corporate operations. "Larry Ellison is a lawnmower" was supposed to be a jeremiad but now it's more like a guiding principle that we browbeat anyone for questioning.
> we shouldn't be against the person who expected an organization with more money than God to uphold a deal for relative peanuts, right?
You're assuming that there was a deal that wasn't upheld. I don't think we have enough information to assess that. This person's blog posts do read as being somewhat unstable. There's even someone in the comments seemingly genuinely trying to be helpful: "Just wondering if you’re BiPolar (like me) and see a different reality than what is real. Been there."
If you take the statement at face value, that does not appear to be the case. If you don’t take it at face value, the underlying presumptions might be a lot of why they may not be employable.
Really depends on your background doesn't it? You could have convictions, be sanctioned, have visa problems, or all kinds of things that are not easily solvable.
Indeed, and this guy's personality seems a little "difficult" which might make the interview process short. I've known people with insane skills who have such weird personalities that they never get hired. Doing remote bug bounty stuff is a blessing for them.
Come on, with these skills you could convince someone to give you a job if you’re on the streets otherwise. You might not be a senior engineer in the exact thing you want but you won’t be on the streets.
We are, quite notably, in a huge hiring crisis where vast numbers of programmers and researchers can't even get interviews. It really is not that simple
Sure sounds like rhetorical questions or attacking the messenger. Someone can think the bounty industry is going to reward them for actually being exceptional and not look soon enough for other options then pivot to a stance that should give them some quick job offers. If I thought I found an intentional back door I would not engage with an embargo system from the same vendor but I am also not them.
> Someone can think the bounty industry is going to reward them for actually being exceptional and not look soon enough for other options then pivot to a stance that should give them some quick job offers
Sure. And that’s a meaningful answer to the question.
“people with values different from yours, presumably” is a condescending nonanswer.
If someone has this kind of exploit and can't get a bug bounty for it, and desperately needs the money, he can sell it for 100k+ in a shady black market
Whether this is a backdoor or not boils down to whatever your usual proclivities about "bug or backdoor" are; it's not like "if microsoft = 1 hack bitlocker" like the tech press seem to love to report.
This is a bug in the NTFS transaction log replay functionality in the Windows Recovery Environment WinRE, where it will read NTFS transaction logs from an external volume and apply them to the mounted filesystem. This allows the attacker to perform an authentication bypass against WinRE. With BitLocker without PIN or Password, _any_ authentication bypass becomes a disk encryption bypass, since the disk is unsealed by the bootloader (this architectural "flaw" is true for Linux with the same configuration, as well, like Ubuntu installed with their newish Hardware Disk Encryption checkbox in the installer).
In lieu of additional evidence, whether you think the NTFS transaction log issue is a planted backdoor or a simple enumeration bug depends on your conspiracy theory level, like most things in exploit development. To me, it seems like a plausible bug. The weaknesses in boot-time unseal are well known and obvious and this is just one of many, so I don't see it as an earth-shattering revelation, although it is a fun bug.
It's very strange that the same component exists in Windows without the issue, though. Like the author, I'm finding it difficult to come up with reasons why they'd be different.
WinRE ending up with a different version of fstx.dll in it seems like a pretty standard Microsoft (or any other big company) thing to have happen? Again, it all comes down to whether you think the drift was a malicious internal fork or a simple mistake. I will say that the functionality being different makes it an inferior backdoor in many ways; especially in Windows land vulnerability researchers are obsessed with binary diffing, and any delta internally would be more likely to be discovered as a backdoor in review too (ie - “hey maybe we should update fstx in winrt finally, let’s review the drift to make sure there’s not going to be a regression, wait a second why did xyz employee add this suspicious looking code”).
A fun next step would be to look at different fstx versions to see if it’s just something that was patched or refactored out at some point. At that point it could be a patch-door (ie an organic bug where the patch was held back by interference), but again, that would be a crappy setup due to the propensity for Windows vulnerability engineers to use binary diffing - if you had the exploit and the power to hold back the patch, it would be way better to hold it back everywhere.
I'm not necessarily suggesting they intentionally made the dll different for RE. The possibility that RE was maliciously backdoored is certainly possible, but there are three plausible other possibilities I can see:
1. A bug was introduced that affects both, and the bug never make it back into the 11 branch
2. There's conditional logic in RE that triggers the issue
3. 11 introduced new behavior that never make it to RE, causing the bug
The fact that 10 is seemingly unaffected is telling. #2 seems very unlikely, because it suggests new conditional logic was added and not tested. #3 seems unlikely because I can't understand why the binaries would be different anyway. #1 seems unusual because it suggests there's no canonical source of truth for the code, which feels very unlikely for bitlocker of all things (where you want everything speaking the same language).
If there's any benign explanation, I suspect it's likely due to incompetence. This feels like such a strange problem to have. I suspect the follow-ups you suggest are going to happen very soon and we'll know more.
We know how PIN-locked BitLocker works, and it requires unwrapping using a key sealed behind a TPM PIN policy and stretching it using the PIN itself. So we can deduce that this would require that:
* The attacker was able to bypass the TPM PIN sealing policy _and_ brute-force the stretching applied to the decrypted key. Brute-forcing the stretch is plausible on a "lots of expensive stuff" timeline but not an easy attack. Bypassing TPM PIN policy across multiple platforms would be something quite incredible. Given that TPMs are implemented by multiple vendors across multiple fundamental architectural approaches, and aren't based on a universal reference implementation, it would be rather bizarre to find a mistake in many or all of them.
* There is a secret volume key stored on a volume which can be decrypted by another mechanism. This would be a backdoor, but seems vanishingly unlikely given the amount of research which has been applied against BitLocker historically.
* The attacker is at some point able to inject something which allows them to observe the victim applying the PIN. There could be an attack here but it isn't nearly as interesting.
If Microsoft wanted a backdoor they don't need to put it in the WinRE environment. They can sign payloads that will pass the TPM and unlock bitlocker, without needing to store anything on your disk.
Except with TPM+PIN, the TPM itself is verifying the PIN before unsealing any keys... so something else must be going on if they're telling the truth about a PIN exploit.
Maybe their alleged exploit doesn't work on a cold boot or has some other non-standard situation.
Yeah man we've been saying negative things about them for like 40 years must we constantly dwell on what they do wrong? It's time we find positive angles
They keep doing negative things that influence the industry and infringe upon the freedoms of hundreds of millions of people. Yes we should keep dwelling on that.
But nothing has changed. It's fair to say it's silly, jeuvenile, but it's also fair to say MS deserve absolutely no normal respect you would pay a turd. Maybe the poster actually is 12 and we all have a right to be 12 for a while. There's always a new generation discovering today what we discovered 30 years ago.
Nothing has changed? Microsoft is a huge open source contributor now, produced one of the largest open source ecosystems in use (.NET) and provides free access to the biggest open source software repositories (GitHub). Sorry to say, but believing nothing with MS has changed is deranged.
Nothing has changed except that it's even worse now than before, and the venue or arena changes every few years (os to developer tools to office to cloud etc). vscode or .net core or whatever you think is so valuable does not make MS your friend any more than giving you free IE did. Come the fuck on. It is beyond ignorant to try to make this argument. (or it's perfectly consistent with having a financial interest)
I guess if there are always new 20 year olds just discovering something, that must mean there are also always new 15 year olds that haven't discovered it yet, and 80 year olds that have gone Dawkins and lost what they had, and the just plain ignorant or unobservant with no real excuse.
No real open source contributor thinks any corporation is "their friend", whatever that means. And yet, it is undeniably true that being a Linux foundation member and contributor, producing and maintaining one of the largest programming language ecosystem and runtimes currently in use, and running the largest open source friendly source code repositories for free, would have been unthinkable under Balmer or Gates' Microsoft, and if you think otherwise, you should look in the mirror for that ignorance you mentioned.
> They had to do the open-source thing for .NET because of external pressure - not because they've changed.
Corporations don't have some innate "essence" that defines their nature, their behaviour is defined by internal and EXTERNAL factors, yes. So what?
The very fact that you recognize that external factors have influenced how they approach open source is a tacit acknowledgement that their behaviour has indeed changed.
> They had to get GitHub because of the eyeballs. It's not some altruistic play.
> produced one of the largest open source ecosystems in use (.NET)
Are they going to ship an official cross platform UI library any time the next century? Decades after the Java lawsuit they still ship only a crippled copy of their scrapped Microsoft JVM for other platforms.
> Microsoft is a huge open source contributor now
Aren't almost all of their contributions for integration with their proprietary technology?
> Sorry to say, but believing nothing with MS has changed is deranged.
Yes, they got worse. They maintained Windows XP for ages and you could actually feel the improvements they shipped. Windows 11 meanwhile makes me wait for them to add a robotic arm with a knife as hardware requirement, to improve the backstabbing experience.
> Are they going to ship an official cross platform UI library any time the next century?
So because they haven't produced your pet project means they haven't changed?
> Aren't almost all of their contributions for integration with their proprietary technology?
No. They didn't have to make .NET cross platform and run equally well on Linux, they didn't have to join the Linux foundation and make contributions to the Linux kernel. There are hundreds if not thousands of examples like this that would have been unthinkable under Gates and Balmer Microsoft.
> Windows 11 meanwhile makes me wait for them to add a robotic arm with a knife as hardware requirement, to improve the backstabbing experience.
Microsoft is much, much larger than just Windows. You seem to have a very limited understanding of everything they do.
The published exploit doesn’t affect Bitlocker with a PIN, without which Bitlocker isn’t secure anyway. The original author claims they have an exploit that also works with a PIN, but hasn’t provided any proof of that.
It is a mandatory requirement for many Department of Defense Contractors. It matters what systems your company interacts with here creating the requirement. The bigger ones just mandate it to save headaches.
Assuming that the PIN version claim is true, it's interesting to think why they would've released a nerfed useless version rather than the PIN version. I have some ideas but they're completely baseless.
And there is a level above PIN with Bitlocker too, you can have a USB stick with a key on it which you use only during boot. I would imagine that is secure from this attack as the data isn't even stored on the device (I hope).
"Security professionals generally recommend avoiding reliance on any single encryption system and instead evaluating well-reviewed full-disk encryption alternatives such as VeraCrypt".
If they put a backdoor into FDE it would make more sense to advise people to stop using windows at all and using Linux instead. If they put a backdoor in FDE you can be sure there is not just one backdoor in the operating system itself. You shouldn't trust proprietary software at all. You shouldn't even trust open source if it isn't properly audited.
Curious to see this take from you! I followed TrueCrypt for years, but always thought it was very strange that they were anonymous, and then the mysterious shutdown happened, and I have no idea what to make of VeraCrypt. It's been in my "possibly good, but too many weird flags around the whole project" bucket.
Anything in particular that makes you wary? I'm aware of the 2016 and 2020 audits (https://ostif.org/the-veracrypt-audit-results/ is the 2016 one, I believe), but those seemed to suggest things were getting better over time. Curious what other signals to look for.
> not with even with your computer would I run VeraCrypt
This has got to be the most surprising encryption-related comment I've ever read from you. Please tell us what you're thinking about VeraCrypt. What would you say about TrueCrypt v7.1a, the last known good release?
I would also love to hear specific opinions about VeraCrypt because I need to get some Windows users to encrypt some of their seldom-used sensitive files, like HR for example.
They can't use age or any other "right answer" tools. I'm talking about people who don't know their own username, people who don't know that their Windows password is the one they use to log into Windows. "Is that for my email?" Just getting them to use a password manager is like arm wrestling an aligator. If VeraCrypt isn't the best option for them, then what is?
Generally I’d say this is what Sharepoint or Box or a more workflow-specific platform is for. You generally don’t want sensitive data living on individual people’s workstations in an enterprise context, you want it somewhere that you can enforce security settings.
My interpretation was that the authors received a National Security Letter and chose to shut down development rather than let their software get backdoored. IIRC the shutdown announcement cited the discontinuation of Windows XP as why the software got discontinued (when it was cross platform and supported newer versions of Windows) and included a step-by-step guide for how to migrate to Bitlocker (a red flag for anyone remotely cynical).
An independent audit of the last version of TrueCrypt was published about a year after the discontinuation. It did not find any significant security issues or backdoors.
One of the greatest cyber security mysteries of our time. Regardless of what actually happened, I hope the author is okay. (The story implied to me that the author was forced to post that, or was disappeared and the website was changed by someone else)
Is there a brand you do have trust in? I’ve kind of thrown my hands up, considered my attack surface is dude stealing my laptop and not the state department wants my 4chan history, and just use the encryption tools provided by Apple and Microsoft
Don't be so sure. Veracrypt is a fork of Truecrypt, which was famously shuttered after security rumours started spreading - all the way to NSA interventions aimed at the developers. One rumour even said they intentionally shut it down to prevent a possible backdoor compromise. Popular encryption tools for public use will always be priority targets for three letter agencies. And there's more than enough legal leeway here to compromise anyone and anything. If it is popular enough for you to see it mentioned outside of dedicated nerd forums, you can bet these agencies already target it.
In my humble opinion US TLAs don't need to touch Veracrypt at all. They are already in Windows, so keymaterial exfiltration is probably a child's play for them.
>In a normal WinRE session, you have a X:\Windows\System32 directory that has a winpeshl.ini file in it
>However, with the YellowKey exploit, it looks like Transactional NTFS bits on a USB Drive are able to delete the winpeshl.ini file on ANOTHER DRIVE
Interesting. I dont know about this environment - some kind of naive file handle contructing/passing? But then, why require a key press during winre reboot?
I wonder how patachable this is. The thousands of winre thumb drives are certainly out of reach; maybe the bitlocker side update the access permissions? Would it require unenc/reenc?
>The thousands of winre thumb drives are certainly out of reach; maybe the bitlocker side update the access permissions? Would it require unenc/reenc?
The part that isn't mentioned is that the win re is privileged because windows stores a decryption key in the TPM that allows win re to decrypt the disk even without the recovery key. That's why the attack requires win re in the first place, rather than booting into an ubuntu live cd or whatever. This also means you don't have to patch all the winRE thumbdrives out there because their secureboot signatures can simply be revoked, meaning they can't pass TPM validation anymore, therefore they won't be able to decrypt any disks.
> This also means you don't have to patch all the winRE thumbdrives out there because their secureboot signatures can simply be revoked, meaning they can't pass TPM validation anymore, therefore they won't be able to decrypt any disks.
WinRE runs internally, not from a thumb drive, which is why the bootloader will unseal the disk for it (just like if you have a systemd recovery set up on a Linux distribution). It doesn't have a separate key or anything, it's just allowed to use the "main" one, by design. Microsoft just need to patch the WinRE partition in a normal Windows Update to fix the NTFS transaction log driver; no Secure Boot revocation or TPM-related changes are necessary (which is good for them, because _that_ would be a disaster).
By and large this whole thing is orthogonal to BitLocker overall; boot-time unsealed BitLocker is vulnerable to any post-bootloader auth bypass by design, and this is a goofy post-bootloader auth bypass bug.
This doesn't sound bitlocker specific, sounds more like a login bypass. If you rely on TPM without PIN then it gets decrypted automatically. This should be fine normally as attackers shouldn't be able to get past login screen. But this exploit shows a way allegedly to get a unrestricted shell in the recovery environment.
The researcher claims a way to bypass PIN too but hasn't revealed it.
I just digged into the exploit a little bit more and what it does it targets BitLocker in TPM only mode. That means that there is no preboot authentication or anything. What happens is secure boot validates the boot chain and the TPM gives out the encryption keys by itself. When you have physical access, it doesn't really make a difference. If there is a stick you can boot from and drop into an emergency shell or if you have to buy a $5 microcontroller and solder it to certain pins on the main board to sniff the TPM keys. What Microsoft is doing here in general they are selling something that is not secure. They are selling it as as full disk encryption but it's not. Someone who can flash a flash drive with an exploit and drop to a shell and use it to browse and copy files. Can also just buy that microcontroller and watch your YouTube with you How to solder. So the "exploit" isn't The problem here the problem is the false sense of security that Microsoft is selling.
>If there is a stick you can boot from and drop into an emergency shell
This won't work because the TPM will only give you the keys if you're booting an "approved" OS, specifically the PCR states that the encryption keys are bound to.
>or if you have to buy a $5 microcontroller and solder it to certain pins on the main board to sniff the TPM keys.
That only works with dTPMs. fTPMs aren't vulnerable to this, and are far more popular than dTPMs.
fTPMs also have similar issues. The real takeaway is that if your threat model includes actors capable of executing attacks against BitLocker you need to put a password/pin on it in addition to the TPM.
I was talking about the signed recovery shell the article is talking about. Sadly most business laptops still use dtpms. Also if they use ftpms you can simply use a ram scraper. The attack surface is huge either way.
Ubuntu also released TPM based FDE a few versions ago. I had these thoughts then and decided against using it. Typing my passphrase on boot is muscle memory and gives me simple security I can trust.
Also can recover data without my mainboard.
Maybe a hybrid (secureboot-TPM+phrase) slot for day to day to also prevent against evil maid attacks, and another slot with a backup passphrase would be acceptable.
>Typing my passphrase on boot is muscle memory and gives me simple security I can trust.
It's not an either-or. You can combine TPM with passwords which makes it far more secure than password alone. A TPM can enforce password guessing limits, otherwise a password needs to be absurdly long to be secure against GPU bruteforcing attacks. It also prevents someone from swapping out the bootloader with a backdoored version that steals your passwords.
>Also can recover data without my mainboard.
You're supposed to keep a backup of the encryption key when using TPM, in case it fails.
Sounds good - which software supports this? Specifically I'd prefer if it would do a composite key derivation in-time rather than "just a pw prompt but TPM has the full key"
> What Microsoft is doing here in general they are selling something that is not secure. They are selling it as as full disk encryption but it's not.
But you can configure Linux LUKS in the exact same way.
This doesn't seem an attack on BitLocker so much as it is an attack on the secure boot chain.
The value of PIN-less unlock is if your threat model is limited to the disk being disposed of or removed from the machine or otherwise separated from the TPM.
Entering a PIN is inconvenient or impossible if more than one user regularly uses the device. Hence, control to validate access is transferred to a trusted OS component.
You are confused. They are not "security" roles, they are compliance roles. That's all most enterprise customers really care about. They satisfied all of the compliance rules, and are following "best practices" (influenced by MS), anything that happens is not their fault.
And having more busywork to do is actually a good thing. Having people employed to do said busywork shows how serious they are about "security", without requiring any skills that are difficult to hire
As opposed to iOS, which does iCloud backups that are not E2E encrypted by default, so that law enforcement can request your chats (except Signal because they opt out), browser history, etc.?
You can enable ADP for E2E encrypted backups, but it's probable not going to help you much, because the people you are communicating with likely didn't.
This is not to defend Microsoft, more to say that all these companies were part of PRISM.
>You can enable ADP for E2E encrypted backups, but it's probable not going to help you much, because the people you are communicating with likely didn't.
That just sounds like a fundamental issue with security in general, not specific to Apple/Microsoft.
My point is that these defaults that look secure to a non-expert, but do not hold up to scrutiny, are probably intentional.
I have found that even many tech people have incorrect beliefs about these things, like assuming that iCloud Backups are E2E encrypted by default or that disabling Allow Apps to Request to Track disables trackers inside apps.
But you are defending MS, conflating a bunch of things, mainly full disk encryption and cloud backups.
There's a big difference between Apples cloud backup which has documented behavior and a backdoor. I'm also fairly confidant in Apple's full disk encryption, they've gone to court to defend it. There also a lot more data points we can use to judge Apple vs Microsoft on privacy and security, and MS comes out looking bad.
I think my message wooshed. I was not comparing disk encryption and iCloud backups. My point is that insecure defaults are Apple and other's alternative to backdoors. They give plausible deniability ("how is someone able to recover their data if they lost their credentials and we used E2E?"), while at the same time satisfying law enforcement, because the vast majority of people is not aware of them.
Another example is WhatsApp on Android, by default when backups are enabled, they are stored unencrypted in Google Drive. A good counter-example is Signal, which opts out of backups on iOS and Android and the only option is to do E2E backups to their own servers.
I'm also fairly confidant in Apple's full disk encryption, they've gone to court to defend it.
FWIW, in the last leaked report, iPhone was not an issue AFU for Cellebrite (macOS is most likely even easier due to looser security):
It's not a matter of belief. Signal does not provide a way for me to download my own messages off my own devices and safely store them using my own secure backup facility.
Obviously Signal don't owe me anything. I'm not paying for the product and I appreciate what it does offer and makes available for free. But it would be much better if it also supported local backups under the user's control.
Shall we have a discussion about the excuse Microsoft gave as to why keys they claimed, back then, were "secondary keys" belonging to Microsoft, were called ..._NSAKEY when a version of Windows NT shipped, by mistake, with debug symbols on?
One time, just freaking one time, a version of Windows shipped with debug symbols on and, by chance, there had to be cryptographic keys named "NSAKEY" in there.
Yeah.
Now that people constantly turning a blind eye on the wrongdoings of the state are of course going to say that it's totally normal and just repeat the, carefully crafted, excuses from Microsoft from back, that it was totally not a backdoor etc.
The bit I never understood in this story is the accidental leak of the debug symbols. Microsoft publishes them anyway. They are not a secret. Back in the day, the symbols shipped on the CD, and they published updated symbol packages for service packs. Nowadays they are published on the web and their debuggers download the symbols automatically.
For enterprise, there seems to be so much money in doing it, that I don't think people are going to start turning it down just because it's troublesome.
You should always assume that US/european corporate protections are backdoored, now MS, a couple days ago we knew about whatsapp, and I would also include all corporate “secure or encrypted” promises, so I would warn against signal, proton, and the likes. This is the work of NSA, providing a “secure” platforms and push it everywhere to get adopted, providing false sense of security, while depreciating the none bugged ones, few weeks ago verascript developer -Mounir Idrassi- complained about having their account blocked, same with wireguard facing similar issues, and if you find it hard to believe, GPG author -Zimmerman- was harassed by the gov because he wrote the encryption and encryption was considered munition, so he was exporting munition!
Lots and lots of smattering around here. If anything, this is a secure boot flaw (and partially TPM), but that is a separate conversation. Also, it's been known for years that TPM based encryption should always be protected with a PIN for truly sensitive data:
https://learn.microsoft.com/en-us/windows/security/operating...
The author claims to be able to bypass TPM + PIN protection, but I seriously doubt it because that would require breaking or exploiting the TPM itself. Perhaps the author was referring to existing fTPM flaws but even then, brute-forcing the PIN would still be required because on BitLocker, the wrapped VMEK depends on the PIN, which brings me to the "backdoor" topic.
As I have already mentioned, exploits have been found in AMD fTPMs in the past (https://arxiv.org/abs/2304.14717). This flaw is particularly severe on Linux/cryptenroll because the TPM returns the actual FVEK, unlike BitLocker, where the VMEK itself depends on the PIN. This cryptenroll flaw has been known for years and remains unfixed on cryptenroll (https://github.com/systemd/systemd/pull/27502). Yet, I see no one yelling and crying "backdoor", or accusing Lennart of being compromised. Cryptography, especially when combined with hardware security, is inherently not easy — and people make mistakes.
As long as Microsoft will continue to use dark patterns to convert local accounts to online accounts and automatically, without user consent, encrypt the storage drives preventing any computer use until the user goes to aka.ms and through the hoops, this is a good thing.
No one should have their data encrypted and kept from them without consent unless they do something. Microsoft does that now. They may not be requring a monetary ransom like others, but it is a ransom nevertheless.
I know this is controversial. Bitlocker helps protect one's property and information when used intentionally. And that being impacted is a shame.
How would a user that never set it up in the first place have a recovery key? I honestly am asking and don't know.
I recently (last week) had to drive over to a parent's house and "fix" their (pre-online accounts) win 11 computer used for sewing because it had become a blue screen saying aka.ms was required. They did not know how it happened and are not very technical users so I imagine they were tricked by some click-through dialog. It is not something they would ever do intentionally. All that computer ever does is run sewing pattern/control software.
I think there's been some miscommunication. If the bitlocker activation happens during tricking the user into going from a local account to online account, it is without the user's consent or real participation. They haven't printed out a copy of the key or moved it to a usb drive. They aren't aware their drives are being encrypted. They can't set up recovery keys now because the computer itself only shows the blue aka.ms screen. None of those 2/4 options are applicable.
There other 2 options are enterprise or online account (the very thing we're talking about) don't apply in this context.
You can set up recovery keys at any point in time, not just at creation. Just because people don't do it doesn't mean it isn't and hasn't been available for almost 2 decades.
And presumably the instructions for this have been on display on our local planning department in Alpha Centauri? If a user isn't even aware that their local disk is being encrypted without their knowledge or consent then why would they think to set up recovery keys?
This is why I have trust issues with anything Microsoft. They keep burning bridges... And well, lots of Corporations keep trusting them. I guess they deserve each other.
This is a serious bug! I've just enabled TPM+PIN on all my Windows Machines (you need a PIN before the boot sequence starts) and enabled BIOS PINs (though those are easily circumvented) and Secure Boot (again, you can get a signed WinRE and still to this exploit). The TPM+PIN setting has no PoC, but the creator hints that it's possible even with this....
Maybe I’m an outlier but I don’t want my drives encrypted at all. I rather have all my data be accessible if things go catastrophic, I.E. having to pull the drive out of a broken computer and put it in another computer to access the files. I just want it to be plug and play.
Cool. Everyone's threat model is different. As long as we're not writing passwords on sticky notes attached to the monitor, I don't think there's any need to be throwing stones.
Sensitive data written down on a sticky note is arguably more secure than that same data sitting on an unencrypted hard drive, at least in a home setting.
Secure rot* variants require UTF-8 and mappings that shift characters between {1,2,3,4}-byte encoded-character-sizes. That varies the message length, which prevents any message-length or traffic analysis.
The Snowden leaks revealed that the NSA is flummoxed on how to tackle variable character lengths. However, they've cracked rot26 using custom ASIC supercomputers, so it should be considered insecure even though it's twice as good as rot13.
Are you saying you bring your desktop on a train ride as well? Laptops with encryption make sense; if you need to encrypt your desktop, I have questions.
I would. It doesn't even require theft. The naive burglary mitigation is just a happy accident.
I want the crypto-shredding retirement of each storage device. I don't assume I can delete/scrub/overwrite at the time a device goes out of service. I have a box of older HDDs that I still have to get around to destroying properly, because they exist from before the days of practical FDE.
I encrypt my desktop. What if someone breaks in and steals it? My tax returns are on there, banking and investment info, etc. And what if I'm careless about disposing of an internal drive in an old machine that's in the closet, etc. I usually drill or sledge drives, but what if I forget? Encrypting all drives makes sense.
My inference machine is the only drive I leave unencrypted, but that's because it has the models on it, llama.cpp, and nothing else, and I want it back up and running services after a power-failure. My other desktops are encrypted to make hard drive disposal easy.
Simple hypothetical: "A disaster hits and the workstation owner is unable to return to the location the workstation is stored. During that time period the workstation is stolen by a gang of looters."
Also a reason to have off-site backups. Many people have done backups to local servers, only to discover that they have no way to recover their data because thieves stole everything.
My data is mundane and mostly my art projects and photography. I don’t believe I am important or interesting enough for someone to do anything with my data if they somehow managed to get it also I don’t have emails, saved passwords, banking info or that kind of sensitive info on my computers so meh I guess.
If "things go catastrophic" your hard drive is not usable at all anymore. At the very least some files can't be recovered at all. So you need backups in any case. Once you have backups, you might as well encrypt your hard drives, especially if you store these in different locations (which you should).
An advantage of encryption is that it makes it easier to give away or resell devices. With recent encryption schemes (well the ones on Linux, given this article), I feel confident that overwriting the encryption keys gets me close enough to not leaking my data once I get rid of an old hard drive.
That’s not true. I’ve had many computers that refuse to turn on and I was able to recover the files by removing the drive and loading it into a USB hard drive reader and recover the files.
Additional problem is if physical access is obtained, illegal material could be covertly added to the drive then picked up by the built in scanners in your OS. Depends on how important you are.
What's not plug and play if using some sensible fde like idk, dm-crypt? You are only a passphrase away from mounting that drive in any other system you plug it into.
That's my question, because my root is encrypted, I move encrypted disks all the time, and have a couple of encrypted external drives. It's trivial.
But I'm sure that some of the millions of things that I've missed as windows has become what it has become makes this simplicity seem like a scifi absurdity. I don't think that they can even log into their own computers without asking Microsoft for permission over the network. I'm sure the idea of encryption must have been overcomplicated to the point of absurdity in order to trap customers too, I just don't know about it.
I suppose you should just count your blessings (of ignorance) and be available to help your friends with cryptsetup if they decide to flee windows.
* Split the recovery key in two, store each half with a different friend. (If you're feeling fancy, XOR the halves and store that with a third friend, then any two out of three will work.)
* Sneak the key into something you know friends/family won't throw away while you're still alive, like stuck to the back of a sentimental photo in a frame.
____
That said, I think I'm wandering from the original "accumulating dusty old drives in a box" scenario, which has a simpler solution: Keep a growing old_drives_keys.txt file on your current (encrypted) main device.
Yep, this is the way. It survives human memory and doesn't depend on software.
If you keep it in a dark environment that's not super humid the ink should last a really long time. Even in non-optimal conditions (NY summers with high humidity, etc.) I've had regular pen ink last for decades with no signs of fading away.
Same here. If anything happens I want a decent chance to be able to recover my data. The most I may do is create encrypted files, and some of them I've forgotten the passwords for, which makes me even more wary.
I was happy to give up my side-hobby of drilling drives after FDE became standard everywhere. Plug and play is great, but you don't want it to be plug and play for whoever pulls your drive out of the trash.
I mean... you can use an encryption scheme compatible with this (if you know the password).
I suppose this makes some sense for home computers (burglars and police raids are rare) but for a laptop, you really don't want thieves getting all your details.
Ironically -- this probably was paranoid a few years ago, but now -- "ChatGPT, use this prepared prompt to extract all useful info from this hard drive"
Title sounds conspiratorial, but it lines up well with the controversy around TrueCrypt's discontinuation which, I believe, specifically called out BitLocker as an alternative to use in future.
Long time ago TrueCrypt suddenly and abruptly shut down with a vague goodbye message saying "everyone please move on and use bitlocker instead"
Prevailing theory is they were pressured to put in a backdoor and couldn't disclose it, so they had to make a seemingly ridiculous statement (because who in their right mind would trust bitlocker) to call attention that "something is very wrong"
>so they had to make a seemingly ridiculous statement (because who in their right mind would trust bitlocker) to call attention that "something is very wrong"
Alternately, they don't want people to rely on abandonware for security.
Also, despite the conspiracy theories of backdoors I'm not aware of any bitlocker exploits that work on TPM + pin, which is the intended "secure" configuration[1]. All exploits rely on TPM-only (ie. ez-mode), which is basically the security equivalent of running https/ssh without certificates and blindly accepting whatever keys shows up.
Why do you need a separate PIN anyway? Shouldn't your Windows password be enough? Having to enter two different codes makes it unlikely a majority would use the system. I would be surprised if iOS or Android required a separate PIN for encryption.
macOS solved this (and a lot of other problems) by putting the OS on a separate read-only partition - technically an APFS volume - that doesn’t get encrypted. Microsoft’s backwards-compatibility obsession might not let them make that the default, but they could at least make it an option.
Not encrypting the OS means it's no longer considered FDE in my opinion.
But Windows doesn't need the OS to decrypt a BitLocker volume anyway because the bootloader can do it... otherwise how could a FDE disk ever boot in the first place?
Why not? The macOS OS partition is signed and read-only. Unless you disable SIP (which you shouldn't), your OS partition is bit-for-bit identical to everyone else's.
Mental inertia. It used to be a bad thing to theorize conspiracies without evidence, but now we actually have evidence of so many conspiracies similar to this that it's probable there are lots more.
This doesn't surprise me at all. Microsoft is a Chinese company and Chinese companies have to work with the government on such matters. Oh sorry, I meant an US company, whatever..
Another way to look at this is that Microsoft, Google, Apple, et al are in the business of providing products and services to regular people, for a low cost. This means they end up providing ways to escrow keys, recover locked accounts and so on that are weak. Not because they want to provide back doors for TLAs but because to provide strong security would be so expensive they couldn't meet the price point for regular customers. If, for example, MS only provided disk encryption that relied on a smart card or a memorized strong passphrase at boot/wake, they'd go out of business providing support to people who forgot their passphrase and being sued by people who lost their data.
> The vulnerability may also work without a USB drive if the FsTx files are copied to the Windows EFI partition and the encrypted disk is temporarily disconnected from the system. After placing the FsTx folder, an attacker would need to reboot a BitLocker-protected machine, enter the Windows Recovery Environment, and follow a specific sequence of inputs.
At the point where you're able to mount the EFI partition and effectively modifying the bootloader, it's game over anyway - just run `manage-bde -unlock`, you already have to be root to mount the EFI partition.
The real problem with a Bitlocker backdoor or weakness is that when a laptop gets stolen or lost, in most regulated organizations, the criteria for legally declaring and disclosing a breach pivots on whether it was protected by disk encryption.
If it's a backdoor, that's a serious fraud against their customers.
This doesn't make much sense. Almost every single organization using Bitlocker knows that it's backdoored. It's like Push Notifications or SMS, warrantless surveillance is the norm and you don't get to opt-out. Nobody's IT department is waking up in cold sweats at the idea of the Fed stealing their data, it's part and parcel with using Windows services.
If you really think this will be prosecuted as fraud, then you'll be shocked by how American courts handle these sorts of things.
if you have ever dealt with a regulated institution, they have an obligation to publicly report lost and stolen devices that contain PII/PHI as a breach, and the people whose data was on the device must be notified. It's a huge deal that has board level involvement when it occurs.
The ONLY control that mitigates this risk is disk encryption, and it is perniciously misleading to ship a sabotaged product on which these legally consequential decisions get made around the world- based on the specific assurance the product is designed and marketed to provide.
If true, it is a specific outrage against the laws of several countries, medical and other research ethics, public health, and the social contracts people have with their institutions. If MS is given impunity for this, a lot of regulation is not worth the paper it is written on.
before arguing further, I recommend looking at the breach notification sections of the laws in these major economies: https://www.dlapiperdataprotection.com/
I commented because I've worked with regulated institutions where FDE was standard across the org. Bitlocker was laughed at whenever you mentioned it by name, there was not a single engineer I met that took it seriously (even the Windows daily drivers). Microsoft Windows is consistently identified as the weakest link for securing sensitive data, one job even had a no-fly policy for Windows laptops in case they were misplaced in luggage.
So remind me how Microsoft was reprimanded for merging Dual_EC_DRBG support into Windows Vista? Or how they were punished for turning over Bitlocker keys to US law enforcement? It never happens. The regulation isn't worth the paper it's written on, and it hasn't been for well over a decade now: https://en.wikipedia.org/wiki/NOBUS
we all know there are limits and vulnerabilities to manage in products. however, this backdoor appears to be a misrepresentation of the core function of the product. if you deployed something you believed to be a joke, you may be the sucker at that table, as thats culpable.
maybe the license language means they make no reps about security, but if this is as described they have compromised the compliance of their customer base.
> Security professionals generally recommend avoiding reliance on any single encryption system and instead evaluating well-reviewed full-disk encryption alternatives such as VeraCrypt.
What does this even mean? Nobody is using multiple encryption schemes on top of each other, are they?
I've heard this before, so what I think it means is this:
If you want to encrypt some data that gets stored persistently somewhere on your machine, rather than invent an application-specific encryption scheme for that data alone, instead use a mainstream full-partition encryption mechanism, then store the data as plaintext within said partition.
Seems bullshit, apparently it only works with TPM-only mode, which is obviously insecure (it relies on neither the OS nor the hardware being exploitable, on a random Windows PC...), and not worth building a backdoor for.
The way one would backdoor something like Bitlocker is to encrypt the disk encryption key with a (post-quantum) public key for which only the backdoor owner has the private key for, and then put it on a place on disk that is unused by the filesystem.
Well I doubt anyone would be surprised with a backdoor in MS product, there have been many of them already, I frankly doubt anyone with "disk encryption" on Windows would think that it's NSA-proof (or script-kiddy clever, as shown in this article :))
