Upset Microsoft stashes hard drive encryption keys in OneDrive cloud?

Let's have a chat about that


Water cooler El Reg, some friends of mine have been showing me blog posts about Microsoft keeping secret copies of all our encryption keys. What's going on?

Since Windows 8, Microsoft has built drive encryption into its operating system, so none of this should really be a shock. And this encryption feature shouldn't be confused with Bitlocker, which is aimed at power users and businesses; think of this feature as a diet Bitlocker.

Whenever you first log into a new Windows 10 computer or device using a Microsoft account, the OS quietly and automatically encrypts the internal storage drive, and uploads a recovery key to Redmond's OneDrive servers. While you're logged into your machine, your data is decrypted and accessible. If someone steals your PC or tablet, and they don't know your password, they shouldn't be able to get at your files because they can't decrypt them.

Why does Microsoft want our recovery keys?

If you forget your password or somehow can't log into your PC or device any more, you won't be able to use your drive because it will remain encrypted. If you change your motherboard, you won't be able to decrypt your data either because the system ties the encryption to a crypto key stored in the chipset. The new board won't have that key.

This still doesn't explain why the recovery key is held in the cloud.

Imagine the tech support calls Microsoft and PC makers must get every day from people – people who think the caps lock key is cruise control FOR COOL. People who can't remember how to turn on Bluetooth. Now imagine the sheer hell of dealing with hundreds of thousands, if not millions, of people who wake up one morning and can't remember their passwords, only to be told: "Sorry, it's gone. All your data is gone."

It's not a hassle Microsoft wants to deal with, so it provides people a recovery key, stored on the corporation's servers, to sign back in. If you have recovery key for an encrypted drive, you can decrypt it.

It was the NSA, wasn't it?

Sure, mate, the NSA.

Can't I just print out my key? Or put it on a USB stick? And not give a copy to Redmond?

Yes – you can print it out or save it to a thumb drive in case you need it in future. You can download your key from here. If you can't see a key, and you're a Windows user, then your computer doesn't have the hardware – such as a suitable TPM module – to support the storage encryption, so you don't have to worry about any of this.

Why didn't Microsoft just tell me this was happening?

Well, here's the rub. Maybe if Microsoft was a little more upfront with people, and made it a clear option during installation or during the first boot, this wouldn't be such a shock. Just like its privacy settings in Windows 10 that are on by default and tucked away: some are useful, others not, but a little warning would have been appreciated.

Well, I don't like it. Whoever has my recovery key can decrypt my drive. I don't want Microsoft to have my key.

Fine. If you're a Windows Home user, click here, save a copy of the recovery key just in case, and then delete it from OneDrive. Microsoft promises to eventually scrub it from its cloud servers and backups.

Beware: if another person logs into your machine using a Microsoft account, the recovery key may be uploaded again. To put an end to this, follow these instructions (skip step four) to create a new recovery password that is just between you and your computer. Obviously, don't lose or forget this password.

Alternatively, switch off drive encryption by opening the Control Panel, and navigating to PC and devices, then PC info, then Device Encryption, and doing the deed there. Now you can use another disk encryption tool that doesn't send keys to off-site systems.

What if I'm using Windows 10 Pro or Enterprise?

Go to the Control Panel, open the Bitlocker settings screen, turn the feature off, then reenable it, and then when prompted, don't allow the recovery key to be sent to Microsoft's servers. Pro and Enterprise editions can also store recovery keys in an Active Directory service, which is an obvious thing to do in a corporate environment.

Look, this is a breach of my privacy – what if the Feds get hold of the recovery key? They have ways and means to do so.

Anyone with the recovery key needs physical access to your machine to use it, so that computer would have to be seized anyway for the key to be any use.

OK, so let's say I'm going through customs and a border officer confiscates my laptop...

If the Feds are in your threat model, shouldn't you try something a little stiffer than the default encryption tool?

I, er, didn't know Windows worked this way.

Sounds like you need to pick another adversary, mate. ®

Similar topics

Broader topics


Other stories you might like

  • Protecting data now as the quantum era approaches
    Startup QuSecure is the latest vendor to jump into the field with its as-a-service offering

    Analysis Startup QuSecure will this week introduce a service aimed at addressing how to safeguard cybersecurity once quantum computing renders current public key encryption technologies vulnerable.

    It's unclear when quantum computers will easily crack classical crypto – estimates range from three to five years to never – but conventional wisdom is that now's the time to start preparing to ensure data remains encrypted.

    A growing list of established vendors like IBM and Google and smaller startups – Quantum Xchange and Quantinuum, among others – have worked on this for several years. QuSecure, which is launching this week after three years in stealth mode, will offer a fully managed service approach with QuProtect, which is designed to not only secure data now against conventional threats but also against future attacks from nation-states and bad actors leveraging quantum systems.

    Continue reading
  • Cheers ransomware hits VMware ESXi systems
    Now we can say extortionware has jumped the shark

    Another ransomware strain is targeting VMware ESXi servers, which have been the focus of extortionists and other miscreants in recent months.

    ESXi, a bare-metal hypervisor used by a broad range of organizations throughout the world, has become the target of such ransomware families as LockBit, Hive, and RansomEXX. The ubiquitous use of the technology, and the size of some companies that use it has made it an efficient way for crooks to infect large numbers of virtualized systems and connected devices and equipment, according to researchers with Trend Micro.

    "ESXi is widely used in enterprise settings for server virtualization," Trend Micro noted in a write-up this week. "It is therefore a popular target for ransomware attacks … Compromising ESXi servers has been a scheme used by some notorious cybercriminal groups because it is a means to swiftly spread the ransomware to many devices."

    Continue reading
  • Europe proposes tackling child abuse by killing privacy, strong encryption
    If we're gonna go through this again, can we just literally go back in time?

    Proposed European regulations that purport to curb child abuse by imposing mass surveillance would be a "disaster" for digital privacy and strong encryption, say cybersecurity experts.

    A number of options have been put forward for lawmakers to mull that aim to encourage or ensure online service providers and messaging apps tackle the "detection, removal, and reporting of previously-known and new child sexual abuse material and grooming."

    These options range from voluntary detection and reporting of child sexual abuse material (CSAM) and grooming, to legally mandating that service providers find and report such material using whatever detection technology they wish — essentially scanning all private communications and, if necessary, breaking end-to-end (E2E) encryption for everyone.

    Continue reading
  • OpenSSH takes aim at 'capture now, decrypt later' quantum attacks
    Guarding against the forever almost-here crypto-cracking tech

    OpenSSH 9 is here, with updates aimed at dealing with cryptographically challenging quantum computers.

    The popular open-source SSH implementation aims to provide secure communication in a potentially unsecure network environments. While version 9 is ostensibly focused on bug-fixing, there are some substantial changes lurking within that could catch the unwary, most notably, the switch from the legacy SCP/RCP protocol to SFTP by default.

    The OpenSSH group warned the change was coming earlier this year, with a deprecation notice in February's version 8.9 release. Experimental support for transfers using the SFTP protocol as a replacement for the SCP/RCP protocol turned up in version 8.7 in August 2021 with the warning: "It is intended for SFTP to become the default transfer mode in the near future."

    Continue reading
  • IBM powers up cloud service for managing crypto keys
    As in encryption, not coins, thankfully

    IBM has unveiled a cloud-based key management service that should make it easier for organizations to manage encryption keys across complex multi-cloud hybrid environments, as well as on-premises.

    The new support comes in the form of the Unified Key Orchestrator, a multi-cloud key management product sold as a managed service as part of IBM's Cloud Hyper Protect Crypto Services.

    Many organizations have by now adopted a multi-cloud strategy, hosting workloads in the most advantageous location, whether that is in a public cloud or in the organization's own datacenter.

    Continue reading
  • Dems propose privacy-respecting digital dollar
    ECASH Act calls for Treasury to develop electronic currency, no blockchain required

    House Democrats on Monday plan to introduce a law bill that calls for the development of an electronic version of the US dollar that has the same legal status and privacy expectations as physical currency.

    The bill, titled Electronic Currency and Secure Hardware (ECASH) Act, would direct the US Treasury Department to establish a program to coordinate the development and implementation of e-cash and the technology necessary to support it, such as cryptographic hardware.

    Sponsored by Rep Stephen Lynch (D-MA), Chairman of the Task Force on Financial Technology, and by Rep Jesús "Chuy" García (D-IL), who serves on the Committee on Financial Services, the ECASH Act represents a response to recent calls by the US Federal Reserve and the Biden administration to promote the development of digital assets.

    Continue reading
  • Samsung shipped '100 million' phones with flawed encryption
    Academics found TrustZone-level code could not be trusted to keep secrets

    Academics at Tel Aviv University in Israel have found that recent Android-based Samsung phones shipped with design flaws that allow the extraction of secret cryptographic keys.

    The researchers – Alon Shakevsky, Eyal Ronen, and Avishai Wool – describe their work in a paper titled, "Trust Dies in Darkness: Shedding Light on Samsung's TrustZone Keymaster Design," which is scheduled for presentation at Real World Crypto and USENIX Security, 2022.

    Android smartphones, which pretty much all use Arm-compatible silicon, rely on a Trusted Execution Environment (TEE) supported by Arm's TrustZone technology to keep sensitive security functions isolated from normal applications. These TEEs run their own operating system, TrustZone Operating System (TZOS), and it's up to vendors to implement the cryptographic functions within TZOS.

    Continue reading

Biting the hand that feeds IT © 1998–2022