12 KiB
title, description, ms.topic, ms.date
| title | description | ms.topic | ms.date |
|---|---|---|---|
| Personal Data Encryption (PDE) | Personal Data Encryption unlocks user encrypted files at user sign-in instead of at boot. | how-to | 03/13/2023 |
Personal Data Encryption (PDE)
[!INCLUDE Personal Data Encryption (PDE) description]
[!INCLUDE personal-data-encryption-pde]
Prerequisites
Required
- Azure AD joined device
- Windows Hello for Business
- Windows 11, version 22H2 and later Enterprise and Education editions
Not supported with PDE
- FIDO/security key authentication
- Winlogon automatic restart sign-on (ARSO)
- For information on disabling ARSO via Intune, see Disable Winlogon automatic restart sign-on (ARSO).
- Windows Information Protection (WIP)
- Hybrid Azure AD joined devices
- Remote Desktop connections
Security hardening recommendations
-
Kernel-mode crash dumps and live dumps disabled
Kernel-mode crash dumps and live dumps can potentially cause the keys used by PDE to protect content to be exposed. For greatest security, disable kernel-mode crash dumps and live dumps. For information on disabling crash dumps and live dumps via Intune, see Disable kernel-mode crash dumps and live dumps.
-
Windows Error Reporting (WER) disabled/User-mode crash dumps disabled
Disabling Windows Error Reporting prevents user-mode crash dumps. User-mode crash dumps can potentially cause the keys used by PDE to protect content to be exposed. For greatest security, disable user-mode crash dumps. For more information on disabling crash dumps via Intune, see Disable Windows Error Reporting (WER)/user-mode crash dumps.
-
Hibernation files can potentially cause the keys used by PDE to protect content to be exposed. For greatest security, disable hibernation. For more information on disabling crash dumps via Intune, see Disable hibernation.
-
Allowing users to select when a password is required when resuming from connected standby disabled
When this policy isn't configured, the outcome between on-premises Active Directory joined devices and workgroup devices, including Azure Active Directory joined devices, is different:
-
On-premises Active Directory joined devices:
-
A user can't change the amount of time after the device´s screen turns off before a password is required when waking the device.
-
A password is required immediately after the screen turns off.
The above is the desired outcome, but PDE isn't supported with on-premises Active Directory joined devices.
-
-
Workgroup devices, including Azure AD joined devices:
-
A user on a Connected Standby device can change the amount of time after the device´s screen turns off before a password is required to wake the device.
-
During the time when the screen turns off but a password isn't required, the keys used by PDE to protect content could potentially be exposed. This outcome isn't a desired outcome.
Because of this undesired outcome, it's recommended to explicitly disable this policy on Azure AD joined devices instead of leaving it at the default of Not configured.
-
For information on disabling this policy via Intune, see Disable allowing users to select when a password is required when resuming from connected standby.
-
Highly recommended
-
BitLocker Drive Encryption enabled
Although PDE will work without BitLocker, it's recommended to also enable BitLocker. PDE is meant to work alongside BitLocker for increased security. PDE isn't a replacement for BitLocker.
-
Backup solution such as OneDrive in Microsoft 365
In certain scenarios such as TPM resets or destructive PIN resets, the keys used by PDE to protect content will be lost. In such scenarios, any content protected with PDE will no longer be accessible. The only way to recover such content would be from backup.
-
Windows Hello for Business PIN reset service
Destructive PIN resets will cause keys used by PDE to protect content to be lost. A destructive PIN reset will make any content protected with PDE no longer accessible after the destructive PIN reset has occurred. Content protected with PDE will need to be recovered from a backup after a destructive PIN reset. For this reason Windows Hello for Business PIN reset service is recommended since it provides non-destructive PIN resets.
-
Windows Hello Enhanced Sign-in Security
Provides additional security when authenticating with Windows Hello for Business via biometrics or PIN
PDE protection levels
PDE uses AES-CBC with a 256-bit key to protect content and offers two levels of protection. The level of protection is determined based on the organizational needs. These levels can be set via the PDE APIs.
| Item | Level 1 | Level 2 |
|---|---|---|
| PDE protected data accessible when user has signed in via Windows Hello for Business | Yes | Yes |
| PDE protected data is accessible at Windows lock screen | Yes | Data is accessible for one minute after lock, then it's no longer available |
| PDE protected data is accessible after user signs out of Windows | No | No |
| PDE protected data is accessible when device is shut down | No | No |
| PDE protected data is accessible via UNC paths | No | No |
| PDE protected data is accessible when signing with Windows password instead of Windows Hello for Business | No | No |
| PDE protected data is accessible via Remote Desktop session | No | No |
| Decryption keys used by PDE discarded | After user signs out of Windows | One minute after Windows lock screen is engaged or after user signs out of Windows |
PDE protected content accessibility
When a file is protected with PDE, its icon will show a padlock. If the user hasn't signed in locally with Windows Hello for Business or an unauthorized user attempts to access PDE protected content, they'll be denied access to the content.
Scenarios where a user will be denied access to PDE protected content include:
- User has signed into Windows via a password instead of signing in with Windows Hello for Business biometric or PIN.
- If protected via level 2 protection, when the device is locked.
- When trying to access content on the device remotely. For example, UNC network paths.
- Remote Desktop sessions.
- Other users on the device who aren't owners of the content, even if they're signed in via Windows Hello for Business and have permissions to navigate to the PDE protected content.
How to enable PDE
To enable PDE on devices, push an MDM policy to the devices with the following parameters:
- Name: Personal Data Encryption
- OMA-URI: ./User/Vendor/MSFT/PDE/EnablePersonalDataEncryption
- Data type: Integer
- Value: 1
There's also a PDE CSP available for MDM solutions that support it.
Note
Enabling the PDE policy on devices only enables the PDE feature. It does not protect any content. To protect content via PDE, use the PDE APIs. The PDE APIs can be used to create custom applications and scripts to specify which content to protect and at what level to protect the content. Additionally, the PDE APIs can't be used to protect content until the PDE policy has been enabled.
For information on enabling PDE via Intune, see Enable Personal Data Encryption (PDE).
Differences between PDE and BitLocker
PDE is meant to work alongside BitLocker. PDE isn't a replacement for BitLocker, nor is BitLocker a replacement for PDE. Using both features together provides better security than using either BitLocker or PDE alone. However there are differences between BitLocker and PDE and how they work. These differences are why using them together offers better security.
| Item | PDE | BitLocker |
|---|---|---|
| Release of decryption key | At user sign-in via Windows Hello for Business | At boot |
| Decryption keys discarded | When user signs out of Windows or one minute after Windows lock screen is engaged | At reboot |
| Files protected | Individual specified files | Entire volume/drive |
| Authentication to access protected content | Windows Hello for Business | When BitLocker with TPM + PIN is enabled, BitLocker PIN plus Windows sign-in |
Differences between PDE and EFS
The main difference between protecting files with PDE instead of EFS is the method they use to protect the file. PDE uses Windows Hello for Business to secure the keys that protect the files. EFS uses certificates to secure and protect the files.
To see if a file is protected with PDE or with EFS:
- Open the properties of the file
- Under the General tab, select Advanced...
- In the Advanced Attributes windows, select Details
For PDE protected files, under Protection status: there will be an item listed as Personal Data Encryption is: and it will have the attribute of On.
For EFS protected files, under Users who can access this file:, there will be a Certificate thumbprint next to the users with access to the file. There will also be a section at the bottom labeled Recovery certificates for this file as defined by recovery policy:.
Encryption information including what encryption method is being used to protect the file can be obtained with the cipher.exe /c command.
Disable PDE and decrypt content
Once PDE is enabled, it isn't recommended to disable it. However if PDE does need to be disabled, it can be done so via the MDM policy described in the section How to enable PDE. The value of the OMA-URI needs to be changed from 1 to 0 as follows:
- Name: Personal Data Encryption
- OMA-URI: ./User/Vendor/MSFT/PDE/EnablePersonalDataEncryption
- Data type: Integer
- Value: 0
Disabling PDE doesn't decrypt any PDE protected content. It only prevents the PDE API from being able to protect any additional content. PDE protected files can be manually decrypted using the following steps:
- Open the properties of the file
- Under the General tab, select Advanced...
- Uncheck the option Encrypt contents to secure data
- Select OK, and then OK again
PDE protected files can also be decrypted using cipher.exe. Using cipher.exe can be helpful to decrypt files in the following scenarios:
- Decrypting a large number of files on a device
- Decrypting files on a large number of devices.
To decrypt files on a device using cipher.exe:
-
Decrypt all files under a directory including subdirectories:
cipher.exe /d /s:<path_to_directory> -
Decrypt a single file or all of the files in the specified directory, but not any subdirectories:
cipher.exe /d <path_to_file_or_directory>
Important
Once a user selects to manually decrypt a file, the user will not be able to manually protect the file again using PDE.
Windows out of box applications that support PDE
Certain Windows applications support PDE out of the box. If PDE is enabled on a device, these applications will utilize PDE.
- Mail
- Supports protecting both email bodies and attachments