Login Failures attack in security log

Question

Hi All,

Any better solution to prevent this attack. I have created Firewall rule to block particular IPs but now attack is coming without IP address.
Any suggestion how to block and prevent this.

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An account failed to log on.

Subject:
Security ID: NULL SID
Account Name: -
Account Domain: -
Logon ID: 0x0

Logon Type: 3

Account For Which Logon Failed:
Security ID: NULL SID
Account Name: it
Account Domain:

Failure Information:
Failure Reason: Unknown user name or bad password.
Status: 0xC000006D
Sub Status: 0xC0000064

Process Information:
Caller Process ID: 0x0
Caller Process Name: -

Network Information:
Workstation Name: -
Source Network Address: -
Source Port: -

Detailed Authentication Information:
Logon Process: NtLmSsp
Authentication Package: NTLM
Transited Services: -
Package Name (NTLM only): -
Key Length: 0

This event is generated when a logon request fails. It is generated on the computer where access was attempted.

The Subject fields indicate the account on the local system which requested the logon. This is most commonly a service such as the Server service, or a local process such as Winlogon.exe or Services.exe.

The Logon Type field indicates the kind of logon that was requested. The most common types are 2 (interactive) and 3 (network).

The Process Information fields indicate which account and process on the system requested the logon.

The Network Information fields indicate where a remote logon request originated. Workstation name is not always available and may be left blank in some cases.

The authentication information fields provide detailed information about this specific logon request.
- Transited services indicate which intermediate services have participated in this logon request.
- Package name indicates which sub-protocol was used among the NTLM protocols.
- Key length indicates the length of the generated session key. This will be 0 if no session key was requested.

Answer 1

Hi. Thank you for your question and reaching out.

Here's how to track down the cause of native AD failed logon attempts.
Step 1: Enable the policy "Audit Logon Events"

-On your Windows server, launch "Server Manager."
-To view the "Group Policy Management Console," choose "Group Policy Management" under "Manage."
-Go to the following links: forest>domain>your domain>domain controllers
-You can update an existing group policy object or create a new one.
-Go to Computer Configuration > Windows Settings > Security Settings > Local Policies > Audit Policy in the group policy editor.
-Select "Audit logon events" under Audit policies and turn on "failure".

Step 2: To identify the cause of failed logon occurrences, use Event Viewer.
Every time a logon attempt in the domain fails, the Event Viewer will now register an event. Take note of event ID 4625, which is set off whenever an unsuccessful logon attempt is registered.

Go to Windows Logs> Security in Event Viewer in Active Directory by opening it. All of the events that have been set up for auditing are listed in the central pane. To find failed logon attempts, you must go through the events that have been registered. When you locate them, you can access more information by selecting Event Properties with the right click on the event. You can find the IP address of the device from which the logon attempt was made in the window that appears.

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Answer 2

Thank you. The server is not in group, it is in workgroup.