We have a 2008 R2 virtual server that is only used for logon via rdp or from local console. No VPN traffic is required.
The server was under attack for a couple of days, viruses where installed etc. Most of it is cleaned up now but i still see many failed logon attempts mostly for user administrator. Logon type of the failed attempts is logon type 3.
From what i understand this (logon type 3) is a logon attempt from the local network. Now i'm trying to disable all logons of type 3 but with no success.
What i have done so far:
disabeled file and printer sharing in the network adapter settings
disabeled windows networking in the network adapter settings
in the advanced sharing settings i disabeled everything (network discovery, file and printer sharing, public folder sharing and password protected sharing)
Also i tried to close some ports that i didn't need, but the login attempts keep coming.
My question:
What can i do to block all login attempts of type 3?
Are there ports i can close?
Other settings that prevent local logons?
Is it possible that these attempts originate from a running program in windows? And if so how can i identify this program?
Other debugging tips?
below an entry from the event log:
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: ADMINISTRATOR
Account Domain:
Failure Information:
Failure Reason: Unknown user name or bad password.
Status: 0xc000006d
Sub Status: 0xc000006a
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
.
