Event ID 4776: Credential Validation Attempt by Computer for User Account

Key Notes

  • Event ID 4776 tracks authentication attempts using NTLM.
  • Failed attempts might indicate unauthorized access attempts.
  • Different error codes provide specific troubleshooting details.

Decoding Windows Security Log Event ID 4776: Implications and Troubleshooting

Understanding Windows Security Log Event ID 4776 is crucial for IT professionals and cybersecurity specialists managing domain controllers and authentication processes. By delving into this log event, we can evaluate potential security threats stemming from failed login attempts and refine our troubleshooting methods effectively.

What is Event ID 4776?

Event ID 4776 is an essential log entry in Windows that captures authentication attempts through the NT LAN Manager (NTLM) protocol. This log is generated in the Domain Controller (DC), confirming whether credentials are successfully validated during logon attempts. It is logged across various Windows platforms including workstations and servers.

Analyzing Event ID 4776 Attempts

Step 1: Validate Using NTLM

When dealing with valid NTLM authentication attempts, identify the involved user or workstation swiftly to trace the source effectively.

Step 2: Investigate Anonymous Logins

If anonymous logon attempts arise or appear to stem from fictitious accounts, pinpoint the source workstation. Consider the following actions:

  • Implement packet sniffers on the domain controller to monitor traffic in conjunction with these events.
  • Utilize a network debugging tool or DCDiag for deeper analysis.
  • Review RDP (port 3389) accessibility; employ firewalls or VPNs to control remote access securely.

Step 3: Review Error Codes

Each error code accompanying Event ID 4776 reveals hints on the status of logon attempts. Evaluate these codes for effective troubleshooting:

Error Code Description
0xC0000064 The username does not exist. Bad username.
0xC000006A Account logon failed due to a bad password.
0xC000006D Generic logon failure – potential username or password issues.
0xC000006F Logon attempts made outside permitted hours.
0xC0000070 Logon from an unauthorized workstation.
0xC0000071 Expired password preventing account logon.
0xC0000072 Account disabled by administrator.
0xC0000193 Account expired.
0xC0000224 Password change required at next logon.
0xC0000234 Account locked.
0xC0000371 Local account store lacks secret information.
0x0 No errors encountered during logon attempts.

Summary

Event ID 4776 serves as a vital tool for IT professionals monitoring authentication processes. By understanding its implications and effectively troubleshooting failures, you can enhance your network security and promptly respond to potential threats.

Conclusion

By staying informed about Event ID 4776, its meaning, and associated error codes, you can take proactive steps in maintaining the security of your network. Understanding the nuances of failed login attempts is essential for preventing unauthorized access and ensuring the integrity of your systems.

FAQ (Frequently Asked Questions)

What does Event ID 4776 indicate?

Event ID 4776 tracks attempts to validate an account’s credentials. Failed attempts can indicate potential security issues.

How does Event ID 4776 differ from Event ID 4624?

While Event ID 4776 signifies authentication failures, Event ID 4624 denotes successful logins.