View source for Forensic: nmap smb-enum-users.nse attack (en)

'''Nmap smb-enum-users.nse''' is a script used to enumerate users on Windows systems with active SMB (Server Message Block) services. This script employs two main methods:

* '''SAMR enumeration:''' This method is subtler and requires fewer packets for each user account. However, the information obtained may not be as complete as that from the LSA method.
* '''LSA bruteforcing:''' This method is noisier, generating more network traffic and log entries. However, it can provide more comprehensive information about user accounts.

==Example Attack==

Suppose we want to enumerate users on a Windows server named "server-windows" that can be accessed from our network. We can run the following Nmap commands:

 nmap -sV --script smb-enum-users.nse server-windows
 nmap --script smb-enum-users.nse -p445 <host>
 sudo nmap -sU -sS --script smb-enum-users.nse -p U:137,T:139 <host>

'''Options used:'''

* `-sV`: Performs version scanning to obtain service version information.
* `--script smb-enum-users.nse`: Runs the smb-enum-users.nse script.

==Expected Results==

The output from the above commands will display a list of users found on the Windows server, including usernames, SIDs (Security Identifiers), and other information.

==Attack Forensics==

If we find evidence of an attack using smb-enum-users.nse, some artifacts we can look for include:

1. '''Nmap Logs:''' If the attacker ran Nmap from an accessible system, we can check Nmap logs to find the commands used.
2. '''System Logs:''' Examine the logs on the target Windows server for suspicious activity, such as failed login attempts or unusual network activity.
3. '''Firewall Logs:''' If there’s a firewall protecting the server, check the firewall logs for suspicious traffic from the attacker’s IP address.
4. '''Network Traffic Capture:''' If we have captured network traffic, we can analyze it for packets related to the smb-enum-users.nse attack.
5. '''Windows Event Logs:''' Check the event log on the Windows server for entries related to user enumeration attempts.

==Mitigation==

To prevent smb-enum-users.nse attacks, several measures can be taken:

* '''Disable Unnecessary SMB:''' If SMB is not needed, disable the SMB service on the server.
* '''Restrict Network Access:''' Limit network access to the server to authorized users only.
* '''Use a Firewall:''' Configure the firewall to block unauthorized traffic.
* '''Update Operating Systems and Applications:''' Ensure that the operating system and applications are always updated with the latest security patches.
* '''Use Strong Passwords:''' Enforce users to use strong and unique passwords for each account.
* '''Enable Audit Logging:''' Activate audit logging features to track user and system activity.

==Important to Remember==

* '''Educational Purpose:''' The above explanation is solely for educational and research purposes. Do not use this information for illegal activities.
* '''Laboratory Environment:''' It’s advisable to conduct these tests in an isolated laboratory environment to avoid unintended consequences.
* '''Permission:''' Always obtain necessary permissions before testing systems that are not owned by you.

==Interesting Links==

* [[Forensic: IT]]	
* '''SMB (Server Message Block):''' Learn in-depth about the SMB protocol, including how it works and common vulnerabilities.
* '''Nmap:''' Explore various features and options of Nmap that can be used for scanning and exploitation.
* '''Network Forensics:''' Study how to analyze network traffic to find evidence of suspicious activity.
* '''Windows Forensics:''' Learn how to analyze Windows systems to uncover evidence of cybercrime.