D
Daniel Demers
i am looking for information on how to discover what process is trying to log into a server. I suspect it has something to do with AD, but that is just a guess, as I cannot see anything out of the ordinary.
Scenario:
We have a Domain environment and a server that is NOT a member of the domain (but I believe it was when it was first deployed, its been a few years). We recently started auditing our logs and this log keeps repeating itself (1-5 times a minute). The log indicates that our PDC server is trying to authenticate to this stand alone server and it attepts to connect to it using random ports.
It almost seems like a brute force attempt from the PDC to the member server, but nothing indicates that there is malicious software on the server.
Log Name: Security
Source: Microsoft-Windows-Security-Auditing
Date: 4/29/2019 11:38:31 AM
Event ID: 4625
Task Category: Logon
Level: Information
Keywords: Audit Failure
User: N/A
Computer: COMPUTER1
Description:
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: MY-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: MY-PDC
Source Network Address: 10.180.10.248
Source Port: 54795
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.
Continue reading...
Scenario:
We have a Domain environment and a server that is NOT a member of the domain (but I believe it was when it was first deployed, its been a few years). We recently started auditing our logs and this log keeps repeating itself (1-5 times a minute). The log indicates that our PDC server is trying to authenticate to this stand alone server and it attepts to connect to it using random ports.
It almost seems like a brute force attempt from the PDC to the member server, but nothing indicates that there is malicious software on the server.
Log Name: Security
Source: Microsoft-Windows-Security-Auditing
Date: 4/29/2019 11:38:31 AM
Event ID: 4625
Task Category: Logon
Level: Information
Keywords: Audit Failure
User: N/A
Computer: COMPUTER1
Description:
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: MY-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: MY-PDC
Source Network Address: 10.180.10.248
Source Port: 54795
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.
Continue reading...