lots of security event 4625??

Question

Hello,
we are in a workgroup environment, based on windows 10 machines. we have a machine that has lots of events (4625), with the following details:

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:       username
    Account Domain:     desktop-name

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:   desktop-name
    Source Network Address: 192.168.1.154
    Source Port:        61546

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.

I would like to know, what would be the exact reason of those events?
Thank you in advance,

Answer 1

Hi,

From the event you shared above, we can only get the following information:
user: username tried to access the computer which logged the events from network with the IP Address: 192.168.1.154
User logon with misspelled or bad user account.
0xC0000064 – “User logon with misspelled or bad user account”.
Especially if you get several of these events in a row, it can be a sign of a user enumeration attack.
0XC000006D – “This is either due to a bad username or authentication information” for critical accounts or service accounts.
Especially watch for a number of such events in a row.
https://learn.microsoft.com/en-us/windows/security/threat-protection/auditing/event-4625

Are there any other events?

Best Regards,