I recently noticed on one of my servers the security log is flooded with 4624 and 4634 events, for type 3 logons under my domain admin account. The server in question is a low volume terminal server, it might average just a half dozen users connecting to it over the course of a 24 hour period. Below is a sample of one of the event log entries. I don't see much in here that helps me figure out where this is coming from, but hopefully someone else will.
An account was successfully logged on.
Subject:
Security ID: NULL SID
Account Name: -
Account Domain: -
Logon ID: 0x0
Logon Type: 3
New Logon:
Security ID: domain\domainadmin
Account Name: domainadmin
Account Domain: domain
Logon ID: 0xa5d57bc
Logon GUID: {999a1d9d-fb64-3719-9aab-5902dad45486}
Process Information:
Process ID: 0x0
Process Name: -
Network Information:
Workstation Name:
Source Network Address: -
Source Port: -
Detailed Authentication Information:
Logon Process: Kerberos
Authentication Package: Kerberos
Transited Services: -
Package Name (NTLM only): -
Key Length: 0
This event is generated when a logon session is created. It is generated on the computer that was accessed.
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 occurred. The most common types are 2 (interactive) and 3 (network).
The New Logon fields indicate the account for whom the new logon was created, i.e. the account that was logged on.
The network 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.
- Logon GUID is a unique identifier that can be used to correlate this event with a KDC event.
- 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.At this point, my security log goes back less than 2 weeks on this server because of these events. In some cases there are 10 or more events in a second. In the last 24 hours, I show 6157 events in the security log. How can I find out what is causing these? Hopefully if I can find the source, I can stop or at least throttle it...