Event ID 4649: A replay attack was detected

Windows Event ID Lookup: What Windows event IDs mean: 4625, 4624, 4740, 6008, 41, 7045, 1102 and 3,000 more, with Windows' own message text, the fields and what to check.

Look up a Windows event ID from Event Viewer, a SIEM alert or a log export: what it means, the fields it records, and what to check. Many IDs are used by more than one source (event 41 is both a Kernel-Power crash and a boot error), so every definition is shown, the one people usually mean first. The message text is Windows' own, read from the event providers of Windows 10.0.26200.0, 2026-10-28; the notes are ours, based on Microsoft's security auditing reference.

Try: 4625, 4624, 4740, 6008, 41, 1074, 7045, 1102, 4104, 1149

A replay attack was detected.

Event 4649

Security-Auditing

Security log

Audit

Message and fields (as Event Viewer shows them)

A replay attack was detected.

Subject:
	Security ID:		…
	Account Name:		…
	Account Domain:		…
	Logon ID:		…

Credentials Which Were Replayed:
	Account Name:		…
	Account Domain:		…

Process Information:
	Process ID:		…
	Process Name:		…

Network Information:
	Workstation Name:	…

Detailed Authentication Information:
	Request Type:		…
	Logon Process:		…
	Authentication Package:	…
	Transited Services:	…

This event indicates that a Kerberos replay attack was detected- a request was received twice with identical information. This condition could be caused by network misconfiguration.