Thanks for the information.
Is there any way to only allow South African IP addresses? (Probably a dumb question).
Also, are we sure that these login attempts are through Remote Desktop? I've pasted one of the Audit Failure logs at the bottom of this post.
I think I'll give the Hetzner firewall a try though. Previously, I wasn't keen since we use a lot of custom ports and it is double work to open the ports on both Hetzner and Windows firewalls, but if I put in strict rules on the Hetzner firewall and I lock myself out, I can also fix it whereas with Windows Firewall, if I'm locked out, I'm screwed.
In the meantime, I've noticed that my remote settings on the server was set to allow connections from computers running any version of Remote Desktop. I've now changed that to only allow for Remote Desktop with NLA.
Strange though. With our first server which I set up from scratch, had a site published on it that even appeared in Google search results, in over 3 years, we've never had these kind of issues / attempts. With this new server, from the first week we've had traffic burst notifications and the only apps & sites on here are "private" (users need to know the specific url or have the proper client software installed in order to access it).
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: db2admin
Account Domain: PC2
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: PC2
Source Network Address: 188.50.6.134
Source Port: 1278
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.
