User enumeration is an important stage in penetration testing where the hacker will use a set of methods to find out valid user names on a company’s network. They will then attempt to use each of these usernames and passwords until they are able to gain unauthorized access to the system. 

User Enumeration:

User enumeration is an important phase in penetration testing that entails identifying valid user names on a company’s network and attempting to use each of these usernames and passwords until they are able to gain unauthorized access to the system. Best practices for user enumeration are as follows:

• Use multiple methods in identifying valid user names, such as the following:
  • Remote command execution. 
  • Port scanning. 
  • Blind SQL injection 
  • Blind LDAP injection 
  • Blind WMI injection 
  • Malicious web application testing 
  • User ID from Facebook, LinkedIn, or Twitter h. Open proxy server 
  • Reconnaissance of social media accounts 
• Ensure that you have obtained all usernames and passwords of valid user accounts on the network.
• In order to avoid detection, avoid using tools such as Metasploit, Wireshark, etc., which can be detected by some antivirus programs. Instead, use these tools during a penetration test to access the internal networks and test systems only.

There are some important facts about user enumeration in Ethical Hacking  are as follows:

• Use static passwords in all important systems without any user name or email address.
• Use it for a single system after enumerating the users.
• Do not use it to administer or change any admin accounts on the company’s network.
• If the system is based on Windows, you can try to get the user’s details via its credential manager service extension.
• You can use CMD or python script to automatically enumerate the users of a system by making multiple connection attempts.
• After gaining access, you need to verify whether the user account is valid or not. If it is valid, then your next target is to gain access to admin-level privilege using a set of tools such as Metasploit with payloads such as Meterpreter, DLL Injection, or Process Manipulation (for example Mimikatz for Windows) in order to carry out a further attack within your target network environment.

Conclusion: 

User enumeration is an important phase in penetration testing that entails identifying valid user names on a company’s network and attempting to use each of these usernames and passwords until they are able to gain unauthorized access to the system. Results will be different depending on the method used by your hackers, however, all methods above can be used to complete this stage of ethical hacking.