Credential Dumping: WDigest

This is our third article in the series of Credential Dumping. In this article, we will manipulate WDigest.dll in order to retrieve the system credentials. The methods used in this article are for both internal and external penetration testing.

Table of Content:

  • Introduction to WDigest
  • Working of WDigest.dll
  • Manual
  • PowerShell
  • Powershell via meterpreter
  • Metasploit Framework
  • PowerShell Empire
  • Mitigation
  • TL; DR

Introduction to Wdigest

WDigest.dll was launched through Windows XP was specifically crafted for HTTP and SASL authentication. Basically, it’s work was to send confirmation of secret keys in order to authenticate the said protocol. The security attributes of NTLM protocol were applied to this DLL file as it’s a challenge/response protocol too. WDigest protocol is enabled in Windows XP — Windows 8.0 and Windows Server 2003 — Windows Server 2012 by default, which allows credentials to be saved in clear text in LSAS file. Windows 10, Windows Server 2012 R2 and Windows Server 2016 doesn’t have this protocol active. And it also released a patch for earlier versions.

Working of WDigest.dll

As it is a challenge-response protocol, it important to understand how it works. Such protocols demand a validating server that creates a challenge for them. The said challenge has incalculable data. A is key is obtained from the user’s password which is further used to encrypt the challenge and to craft a response. A reliable service can then validate the user processes by comparing to the encrypted response that is received by the client and if the responses match, then the user is authenticated.

Now that we have understood what exactly a WDigest protocol is and how it works, let’s get to practical of how to exploit it.

Manual

Our first method to exploit WDigest in to dump the desired credentials is manual. Such a method comes handy in white box pentesting. In this method, download mimikatz and run the following commands :

As you can then see that the result of the above commands didn’t bear a fruit because WDigest protocol wasn’t active. To activate the said protocol, use the following command:

The above command will create a file called UseLogonCredetnial in the WDigest folder in the registry and simultaneously sets it binary value to 1 as you can in the image below:

The above step has just enabled WDigest in the system. Which will allow the password to be saved in memory that too in clear texts. And now these passwords can be retrieved sneakily as you will see further in this article.

For now, we need to update the policy that we just entered in the registry using the following command:

Now, if you launch mimikatz and run the following commands then you will have the credentials.

PowerShell

In this method, we will be invoking PowerShell scripts in the system. This script will further help us get our hands on the credentials.

Download WdigestDowngrade.ps1

Simply launch the PowerShell Command Prompt and run the following commands:

Once the above commands are executed successfully, run the following command to dump the credentials.

And as you can see, we got the credentials.

PowerShell via Meterpreter

In this method, we will be invoking PowerShell script in our meterpreter session. This script will further help us get our hands on the credentials. When you have a meterpreter session, run the following commands to create the UseLogonCredential file and make changes in the registry key.

After the above commands create the UseLogonCredential file as required and then you can launch mimikatz to dump the credentials using the following commands:

Download Invoke Mimikatz.ps1

Metasploit Framework

Our next method is an excellent method to dump the credentials remotely which often a requirement in grey box pentesting. Once you have your meterpreter session via Metasploit, remember to background the session and then you can execute wdigest_caching exploit to make the changes in WDigest folder which we just did manually in our previous method by using the following commands:

Then further use the load kiwi module to dump the credentials. For doing so, type :

And yes! We got our credentials.

PowerShell Empire

When you have a session through Empire, use the post exploit wdigest_downgrade to create the UseLogonCredential file in wdigest folder and its registry key value i.e. 1 with the help of following commands:

Once the above post exploit is executed successfully, you can use another build in post exploit to dump the credentials with the following set of commands:

And after the execution of the above command, you have the credentials.

Mitigation

Following are the steps one can take in order to secure themselves from this scenario:

  • Make sure the there is no UseLogonCredential file in your system
  • If you are using the older versions of windows then make sure that windows us updates with the patch
  • UseLogonCredential registry keys values should be set to 0 to completely disable this protocol.
  • Regularly check the registry key value to make sure that you have not been the victim. 

TL; DR

Understanding the very basics of your operating systems such as windows, allow you to be more secure in this cyber world. Knowing how endpoints are put together to work perfectly for your convenience is important as a seemingly minor change can make you vulnerable. Such as WDigest saves all the passwords in memory on the clear text which puts the credentials of the user at risk. And this thought made us take a stab on credential dumping by manipulating WDigest. So, through with mimikatz, Metasploit framework and other such tools that we have mentioned above can leverage your credentials both locally and remotely and can even allow the attacker to use them to their advantage. An attacker who is able to get administrator privileges of your system can modify the values in the registry and dump the credentials as shown in the article above using Mimikatz, Metasploit, Empire, and PowerShell scripts.

AuthorYashika Dhir is a passionate Researcher and Technical Writer at Hacking Articles. She is a hacking enthusiast. contact here

Credential Dumping: Windows Credential Manager

In this article, we learn about dumping system credentials by exploiting credential manager. We will talk about various methods today which can be used in both internal and external penetration testing.

Table of Content:

  • Introduction to credentials manager
  • Accessing credential manager
  • Metasploit
  • Empire
  • Credentialfileview
  • PowerShell
  • Mitigation
  • Conclusion

Introduction to Credential Manager

Credential Manager was introduced with Windows 7. It is like a digital vault to keep all of your credentials safe. All of the credentials are stored in a credentials folder which you will find at this location – %Systemdrive%\Users\<Username>\AppData\Local\Microsoft\Credentials and it is this folder that credential manager accesses. it also allows you to add, edit, delete, backup and even restore the passwords.

Credentials saved in credential manager are of two types:

  • Web credentials: As Edge and widows are the product of the same company, credentials manager has access to the stored information of Edge browser too, in order to increase safekeeping of saved credentials. It also stores the password of order application provided by Microsoft such as skype, Microsoft office, etc.
  • Windows credentials: Under this category, all the windows login credentials can be found. Along with any system that is connected in the network.

Applications which are run by windows and has your credentials saved will automatically be saved in credential manager. Even when you update them, change is noted by and updated in credential manager too.

Accessing Credential Manager

To access credential manager, you can simply search it up in the start menu or you can access it bu two of the following methods:

  • You can open control panel > user accounts > credential manager
  • You can also access it through the command line with the command vaultcmd and its parameters.

When you connect to another system in the network as using any method like in the following image:

And while connecting when you provide the password and store it for later use too then these credentials are saved in credential manager.

Irrespective of website and its security, when you save any password in the edge or any other application such as skype or outlook, it’s password too gets saved in credential manager. For instance, we have stored Gmail’s password in our practice as shown in the image below:

You can confirm from the following image that the password is indeed saved.

And now, when you access credential manager, using any method, you will find that in windows credentials tab all the system, network passwords are stored.

And under the web credentials tab there are will be application’s passwords and the passwords saved in edge will be saved.

Metasploit

Now all these credentials can be dumped with simple methods. Once you have a session through Metasploit, all you have to do is upload mimikatz and run it. Mimikatz is an amazing credential dumping tool. We have covered mimikatz in detail in one our previous articles, to read that article click here.

And to run mimikatz remotely through Metasploit session, use the following command:

And once the mimikats is executed successfully, you will get credentials from cred manager as shown in the image above.

Empire

Similarly, while using empire, you can dump the credentials by downloading Lazagne.exe directly in the target system and then manipulatinthe lagazne.exe file to get all the credentials. LaZange is on eof the best credential dumping tool. We have covered LaZagne in detail in one our previous articles, to read that article click here.

Use the following commands to dump the credentials with this method :

After the execution of commands, you can see that the passwords have been retrieved as shown in the following image:

CredentialsFileView

Our next method is using a third-party tool, i.e. credentialfileview. This tool is very effective when it comes to internal penetration testing. To use this tool, simply download it and launch it. After launching itself, it will ask you for the windows password.

Once you provide the password, it will give you all the credentials you need as shown in the image below:

Windows PowerShell

This method of password dumping can prove itself useful in both internal and external pentesting. In this method, you have to run a script in windows powershell. You will find the script here. And once you run the script you will have all the web credentials as shown in the image below:

You can also use powershell remotely to dump credentials with the help of Metasploit. It is very simple as you just have to run a combination of following commands after you have your session:

And just like that with the help of powershell commands, you will have the desired credentials.

Mitigation

Following are the measures you can use to keep your passwords safe:

  • DO NOT save passwords in your system, browser or any other application
  • Use different passwords for every account
  • If you have trouble remembering passwords then instead of keeping them in clear text in your system, use an online password manager to keep them safe.
  • Use the latest version of the operating system and applications.
  • Manually go to the login page instead of following a link.
  • Keep firewall/defender enabled
  • Keep you employees/employers aware

Conclusion  

As you have noticed from our article the even though this feature of credential manager that is provided by windows is convenient, it is not secure and once the attacker has the access of your system then these credentials are waiting to be theirs as there is no security layer added to credential manager. It is important to be aware of every feature your operating system is providing just so you can save yourself. Hence, it is important to know how to access the credential manager and how to operate it and how it can be exploited.

We live in a cyber active world and there are login credentials for everything, one can’t remember every credential ever. Though credential manager is utility makes it easy for us and takes the responsibility of saving the passwords, but at what expense?

We at Hacking Articles want to request everyone to stay at home and self-quarantine yourself for the prevention against the spread of the Covid-19. Take Care and be Healthy and Keep Hacking!!

AuthorYashika Dhir is a passionate Researcher and Technical Writer at Hacking Articles. She is a hacking enthusiast. contact here

Persistence: RID Hijacking

In this post, we will be discussed on RID hijacking which is considered to be as a persistence technique in terms of cyber kill chain and in this article, you will learn multiple ways to perform RID hijacking.

Table of Content

Introduction

  • FSMO roles
  • SID & RID
  • Syntax
  • Important Key points

RID-Hijacking

  • Metasploit
  • Empire

Introduction

Microsoft divided the responsibilities of a DC into FSMO roles that together make a full AD system, FSMO (Flexible Single Master Operation) has 5 responsibilities for forest and domain.

  • Schema Master (one per forest)
  • Domain Naming Master (one per forest)
  • Relative identifier (RID) Master (one per domain)
  • Primary Domain Controller (PDC) Emulator (one per domain)
  • Infrastructure Master (one per domain)

SID & RID

The RID is a Relative Identifier which is the last part of SID (security identifier) and should be unique for a particular object within a domain. Each security principal has a unique SID that is issued by a security agent. The agent can be a Windows local system or domain. The agent generates the SID when the security principal is created. The SID can be represented as a character string or as a structure.

Syntax

Syntax: S-[Revision]-[IdentifierAuthority]-[SubAuthority0]-[SubAuthority1]-…-[SubAuthority[SubAuthorityCount]](-RID)

Eg: S-1-5-21-1543651058-3042185658-368006193-1001

Important Key points

  • The revision is always 1 for current NT versions.
  • When a new issuing authority is established under Windows (for example, a new computer is deployed or a domain is established), a SID with an arbitrary value of 5 is allocated as an identifier authority.
  • A constant value of 21 is used as a particular value for the root of this group of sub-authorities, and a 96-bit random number is generated and parcelled out to the three sub-authorities with each sub-authority having a 32-bit chunk.
  • If the new issuing authority under which this SID was developed is a domain, this SID is referred to as the “SID domain.”
  • Windows allocates RIDs starting at 1,000; RIDs that have a value of less than 1,000 are considered reserved and are used for special accounts.
  • For example, all Windows accounts with a RID of 500 are considered built-in administrator accounts in their respective issuing authorities.

RID Hijacking

‘RID Hijacking’ is a tactic for an adversary to persist inside the victim’s system by hijacking the RID the Administrator account for the Guest account, or another local account. Creating persistence in the victim’s system allows an adversary to establish a foothold, continuously regaining access that will be unseen to you and allow to hijacker to logon as an authorized account which adversary has hijacked.

Thus, for this, you need to have privilege account session as we have in the below image, to establish persistence access.

Rid-Hijacking: Metasploit

So, as you know, we had meterperter session with admin privilege and Metasploit provides a module to create persistence in a victim’s machine by hijacking RID of administrator user.

 This module will create an entry on the target by modifying some properties of an existing account. It will change the account attributes by setting a Relative Identifier (RID), which should be owned by one existing account on the destination machine. Taking advantage of some Windows Local Users Management integrity issues, this module will allow authenticating with one known account credentials (like GUEST account), and access with the privileges of another existing account (like ADMINISTRATOR account), even if the spoofed account is disabled.

Once you run the exploit, it will check the status of the guest account and, if it is found to be disabled, it will activate the account first and overwrite the RID value from 501 to 500, i.e. the RID value of the administrator account.

As you’ve seen in the above step, the guest’s RID is 500 and the password is 123, so we logged in as a guest to get the CMD with Administrator privilege on the target machine. Here we are going to use the impacket tool to get the CMD shell of the remote machine.

As you can observe that we have obtained CMD Shell as “nt authority /system” i.e CMD as an administrator account.

Rid-Hijacking: Empire

RID hijacking is also possible using empire but this module is not available in Empire project you need to clone it module from Github.

once both programs get downloaded, fetch the Invoke-RIDHijacking.ps1 file from inside /RID-Hijacking/modules/empire/data/module_source/persistence into /root/Empire/data/module_source/persistence.

Also copy the rid_hijack.py from /RID-Hijacking/modules/empire/lib/modules/powershell/persistence/elevated into /root/Empire/lib/modules/powershell/persistence/elevated

Once you are done with configuration, then launch the module to start the attack, this will initialise the just like Metasploit. First, identify the status of the guest account and then hijack RID =500 for guest user.

Again repeat the above step to connect CMD of victim’s machine assure that you should have a privilege shell.

Reference

https://docs.microsoft.com/en-us/openspecs/windows_protocols/ms-azod/ecc7dfba-77e1-4e03-ab99-114b349c7164

Author: Geet Madan is a Certified Ethical Hacker, Researcher and Technical Writer at Hacking Articles on Information SecurityContact here

Comprehensive Guide on CryptCat

In this article, we will provide you with some basic functionality of CryptCat and how to get a session from it using this tool.

Table of Content

  • Introduction
  • Chat
  • Verbose mode
  • Protect with Password
  • Reverse Shell
  • Randomize port
  • Timeout and Delay interval
  • Netcat vs CryptCat 

Introduction

CryptCat is a standard NetCat enhanced tool with two-way encryption. It is the simplest Unix utility tool, which reads and writes data across network connections. It can use TCP or UDP protocol while encrypting the data that is transmitted over the network. It is a reliable back-end tool that is easily driven by other programs and scripts. It is considered to be a network debugging and exploration tool.

CryptCat can act as a TCP/UDP client or server when connected to or when it acts as a listener to the socket. It can take a password and adds a salt to encrypt the data that is being sent over the connections. Without providing a specified password, it will take the default password i.e. “metallica”.

We can explore its working and usage by exploring its available options.

Chat

CryptCat can be used to chat between two users. We need to establish a stable connection before the chat. To do this, we need two systems out of these two systems one will be a listener and the other will be an initiator. So that communication can be done from both ends.

Here, we are trying to create a scenario of chat between two users with different operating systems.

User 1

OS: Kali Linux

IP Address: 192.168.0.107

Role: Listener

To initiate listener in Kali Linux, follow this command to create a listener:

User 2

OS: Ubuntu

IP Address: 192.168.0.108

Role: Initiator

To create an initiator, we will just provide the IP Address of the system where we started the listener followed by its port number.

Verbose mode

In CryptCat, the verbose mode can be initiated by using the [-v] parameter. Now, the verbose mode is made for generating extended information from our actions. We will try the above chatting mechanism with verbose mode. We can see that when we add [-v] to the CryptCat command it displays the information about the process that its performance while connecting.

At Listener Side

At Initiator Side

Protect with password

In CryptCat, we can protect our connection of chatting with a password and password can be applied by using the [-k] parameter. We know that CryptCat provides us end to end encryption, but by using the [-k] parameter we can provide the extra layer of protection to our connection. So that it is almost impossible to decrypt our connection. We can apply for this protection with the following commands.

At listener side, we apply [-k] parameter along with the password.

At the Initiator side, we need to apply the same password applied by the listener so that we can connect to some connection.

Reverse shell

A reverse shell is a type of shell in which the target machine communicates back to the attacking machine. The attacking machine receives the connection through a port by providing a password. To activate the listener on the target machine for getting shell, use the following command:

Now, at the attacker side, we just need to connect to the victim. Then we can authenticate our self as we got its root access or by the help of whoami command.

Randomize port

If we cant decide our port number to start the listener or establish our CryptCat connection. Well then, CryptCat has a special [-r] parameter for us which gives us a randomize local port.

Timeout and Delay interval

Most of us are confused between these terms. Timeout is supposed to be a time to complete our task or program. Whereas the delay interval is the interval time between two individual requests or tasks. So in CryptCat, we have [-w] parameter for timeout and [-i] parameter for delay interval. To apply these two individual parameters to get our desired results.

At listener side, we apply both times out and the delay interval

At the initiator, we are only applying timeout.

Netcat vs CryptCat

Well before comparing these two first, we need to know about the Netcat or nc. It is a utility tool use TCP and UDP connection to read and write in a network. It can be used for both security and hacking purposes.

In the case of hacking, it can be used with the help of scripts which makes it quite dependable. And if we need to talk about security, it helps us to debug the network along with investing it. If we want to learn all the working of the Netcat. We have covered netcat in our previous article and to read that article click here.

And when it comes to CryptCat, it is a more advanced version of Netcat. It provides us with the two-way encryption that makes our connection more secure. We are comparing these two amazing tools based on connection encryption of the chatting feature by intercepting their network interface with the help of Wireshark.

Netcat:

As we know we apply a listener and an initiator to start this connection for chatting. Along with that, we initiated the Wireshark to intercept its network interface.

At the listener side, we are using [-l] parameter for listening and [-p] parameter for the port number.

At the Initiator side, we just need to provide a port number, along with the listeners IP Address.

Now, we have to check whether our Wireshark was able to catch something or not. As we can see that we successfully intercepted the network and see this network chat.4

Cryptcat:

In cryptcat, we already know that it provides us with two-ways encryption. Which makes the connection network more secure that Netcat. But we need to check this as well by intercepting its chatting with the help of Wireshark. For that connection, we needed a listener and an initiator for connecting a connection.

At the Listener site, we will use the [-p] parameter for port and [-l] for initiating the listener.

At the initiator side, we just need to provide IP Address along with listeners port number.

Now check whether we can acquire anything or not. As we can see that this chat is in encrypted mode.

That is the main difference between the Netcat and the Cryptcat. One provides encryption in its network and the other is not. Some people might say that CryptCat = encryption + Netcat.

Author: Shubham Sharma is a Pentester, Cybersecurity Researcher, Contact Linkedin and twitter.