{"id":225,"date":"2024-05-24T06:21:23","date_gmt":"2024-05-24T06:21:23","guid":{"rendered":"https:\/\/www.lepide.com\/cyber-learning\/?p=225"},"modified":"2024-05-24T06:21:24","modified_gmt":"2024-05-24T06:21:24","slug":"what-is-a-dcsync-attack","status":"publish","type":"post","link":"https:\/\/www.lepide.com\/cyber-learning\/what-is-a-dcsync-attack\/","title":{"rendered":"What is a DCSync Attack?"},"content":{"rendered":"\n
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How Common are DCSync Attacks?<\/h2>\n\n\n\n

DCSync attacks are a relatively common form of credential dumping, often used to maintain persistence or elevate privileges. DCSync is employed by various threat actors, including well-known groups and campaigns such as LAPSUS$ and Solar Winds.<\/p>\n\n\n\n

While not a necessary component of every attack, DCSync is often used when an attacker has gained access to an Active Directory account with elevated privileges, such as membership in groups like Administrators, Domain Admins, or Enterprise Admin.<\/p>\n\n\n\n

In many cases, attackers may already have what they need, making DCSync unnecessary. However, a more common scenario involves accounts delegated “Replicating Directory Changes” permissions, which are often granted to applications that integrate with Active Directory. For example, an attacker may leverage an Azure AD DS Connector account to perform a DCSync attack.    <\/p>\n\n\n<\/div>\n\n\n

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How Does a DCSync Attack Work?<\/h2>\n\n\n\n

A DCSync attack is a type of attack that can be performed using various tools, including mimikatz, Impacket’s secretsdump, and DSInternals’ Get-ADReplAccount. The attack involves using credentials from an account with specific permissions to replicate domain controller data, which does not require an interactive logon to a DC. The required permissions include reading all user and computer objects, group objects, and domain controllers, as well as the ability to add and remove groups and members.<\/p>\n\n\n\n

The attack can be launched from a remote DC, a configuration option in each tool, or from any machine on the network. The goal of the attack can be to target a specific user account or dump the entire Active Directory (AD) to a file.<\/p>\n\n\n\n

The attack process involves the following steps:<\/p>\n\n\n\n

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  1. The attacker identifies a domain controller to request replication.<\/li>\n\n\n\n
  2. The attacker sends a GetNCChanges request to the DC to request user replication data.<\/li>\n\n\n\n
  3. The DC returns the replication data to the requestor, including password hashes.<\/li>\n<\/ol>\n\n\n\n

    The attack requires the following rights:<\/p>\n\n\n\n