Forensique

Post compromission

En cas de compromission, il est intéressant de valider la présence ou non des actions suivantes:

  • Reset all user account passwords twice (thanks @tazwake)
    • Reset all administrator passwords
    • Reset all service accounts passwords
  • Reset (twice – but bear in mind the issues with replication so there’s specific guidance on this) the KRBTGT password
  • Reset all computer account passwords
  • Check the value of the computer account password change value
  • Reset all LAPS Passwords
  • Reset permissions on AdminSDHolders object
  • Revoke and re-issue all certificates from ADCS
  • Check for malicious scheduled tasks (thanks @SchizoDuckie)
  • Check for malicious WMI event filters
  • Check for malicious autoruns or other registry-based persistence mechanisms
  • Check for utilman style backdoors
  • Check for malicious printers/printer drivers (thanks @SchizoDuckie)
  • Review Active Directory Delegated access permissions (thank https://twitter.com/@indachtig)
  • Rotate ADFS token signing and token decryption certificates (thanks @4n6Bexaminer)
  • Check Service Control Manager (SCM) security descriptors (https://docs.microsoft.com/en-us/windows/win32/services/service-security-and-access-rights) (thanks @EricaZeli)
  • Check for object changes around initial access/event timescales (thanks @IISResetMe)
  • Validate group memberships against known baselines (replication metadata, backup, AD reporting tools/reports etc.) (thanks @IISResetMe)
  • Harden Active Directory (look at pingcastle and MITRE) (thanks @MarkSewe)
  • Review logon scripts in GPOS and SYSVOL (thanks @CisoDiagonal and A-HAX!)
  • Rotate Group Managed Service Accounts (GMSA) (thanks @infosecspy)
  • Rotate LAPS credentials
  • Review Azure AD/AD Connect (thanks @infosecspy)
  • Harden Endpoints
  • Update AV
  • Deploy EDR
  • Deploy SYSMON
  • DNS Zone Integrity (Public and Private) (thanks to @jermuv)
  • Rote domain trust keys (thanks @DebugPrivilege)
  • Review potential RBCD Bakdoors (thanks @DebugPrivilege)
  • Review msDsConsistencyGuid attribute of compromised accounts (thanks @DebugPrivilege)
  • Check Exchange (easy right?)
  • Review accounts for “Key Trust Account Mapping” takeover and reset if required (thanks @nodauf)
  • Review Active Directory Domains and Trusts (thanks @dragon199421)
  • Deploy new Domain Controllers (keep existing forest/domain metadata)
  • Clear VSS/Backups/Snapshots that are likely to be classed as unsafe (thanks to @Digit4lbytes)

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