Summary

  • A new attack technique has been discovered called DCSync, which abuses legitimate Active Directory replication mechanisms.
  • This allows an attacker to simulate the behaviour of a Domain Controller and request password hashes from other DCs.
  • This is accomplished by leveraging the Directory Replication Service Remote Protocol, which is used by DCs for replicating directory data.
  • This stealthy method of obtaining credentials provides a pathway for full domain compromise and enables the attacker to achieve complete lateral dominance within a network.
  • It is recommended that organisations review the security of their Active Directory services to ensure they are not susceptible to this type of attack.
  • Additional vigilance is advised, and steps should be taken to protect sensitive information and assets. Mimikatz, a popular password-dumping tool, has adapted its mechanisms to exploit MS-DRSR through two specific RPC calls: IDL_DRSCrackNames and IDL_DRSGetNCChanges.
  • This allows it to retrieve credential material, providing attackers with privileges like replicating directory changes and replicating directory changes all.
  • Ensuring these privileges are restricted to trusted hosts and users is essential to mitigate the risk of a DCSync attack.

By Rushabh Bhutak

Original Article