> For the complete documentation index, see [llms.txt](https://omar-4.gitbook.io/omar-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://omar-4.gitbook.io/omar-docs/ecir/event-codes/dcsync-activity-detection/event-id-4625.md).

# Event ID 4625

As an **Incident Responder (IR)**, you should pay attention to **Event ID 4625** because it records **failed login attempts** (specifically, failed account logons) in Windows environments. This event can be particularly useful for detecting **DCSync attacks** — a type of attack where an adversary attempts to request **Active Directory replication data** (specifically the **NTLM password hashes** and **Kerberos keys**) from a Domain Controller (DC) by impersonating another domain controller or using malicious tools.


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