And now we can use this list of passwords for a dictionary attack on the NTLM hashes. But passwords recovered from NTLM hashes can contain lowercase and uppercase letters. So we need to generate all possible combinations of lowercase and uppercase letters for our password list. This can be done with the toggle rule file toggles-lm-ntlm.rule I created with this new tool.
Crack Lm Hash Nt Hash Decrypt
In Windows NT Microsoft introduced the newer NTLM hashes type, which is essentially the MD4 algorithm (so would not be considered secure by modern standards). NTLM fixed the main two problems with LM hashes (case sensitivity and splitting passwords), so in a major improvement in those respects. However, it lacks many of the features of modern hashing algorithms such as Bcrypt or PBKDF2, such as being slow, salting and GPU/FPGA/ASIC resistant.
John gives you a great deal of customisation, and supports a lot of different cracking modes and hash types. You can also chain together different modes (such as a combined wordlist and mask attack, or applying rules to a PRINCE attack). It can comfortably handle large (multi GB) wordlists and pwdump files (hundreds of thousands of users). Because John has been around for so long there are lots of other tools that are designed to work with it (and its output).
Part 3 of this series explores some of the different tools and techniques that can be used to obtain useful metrics from cracked password hashes in order to determine improvements to a password policy.
The LAN Manager (or LM) hashing algorithm is the legacy way of storing password hashes in Windows. The replacement (NTLM) has been around for quite a while, but we still see the LM hashing algorithm being used on both local and domain password hashes.
The LM hash format breaks passwords into two parts. Each part can be up to seven characters long. If the password is seven characters or less, the second part is just a blank LM hash. All of the alphabetical characters are converted to upper case, as the LM hash standard is case insensitive. Case sensitivity is stored in the NTLM hashes.
For this test, I generated a set of 100 LM/NTLM hashes from randomly generated passwords of various lengths (a mix of 6-14 character lengths). Cracking with Rainbow Tables was done from my Windows laptop (2.70GHz Intel i7, 16 GB RAM, SSD). GPU cracking was done on our GPU cracking box (5 GPUs).
The Windows XP passwords are hashed using LM hash and NTLM hash (passwords of 14 or less characters) or NTLM only (passwords of 15 or more characters). The hashes are stored in C:\WINDOWS\system32\config\SAM. The SAM file is encrypted using C:\WINDOWS\system32\config\system and is locked when Windows is running. This file is a registry hive which is mounted to HKLM\SAM when windows is running. The SYSTEM account is the only account which can read this part of the registry. To get the passwords, you need to shutdown Windows, decrypt the SAM file, and then crack the hashes. If everything goes well, you'll have the passwords in 15 minutes.
Mac OS X 10.4 (Tiger) improves the security by only storing LM+NTLM hashes for users who enable Windows Sharing for their account; and when they do enable it, it asks them to enter their password with a warning that their password is stored in a less secure format. However, for those users with Windows Sharing enabled, the above method will still work. The shadow file format is a little different, but the LM+NTLM hashes are still the first 64 characters. If the hashes are not stored, you will get all 0's when you try to retrieve the hashes.
In older versions of Samba, the password hashes for Samba users were stored in the file /etc/smbpasswd (location may vary, only root has access) and are in similar format to Windows password hashes discussed above. In newer versions of Samba, run the following as root to get the same information:
In a domain environment, the only different is that the server would forward the username, nonce, and encrypted nonce to a domain controller, where the DC could use the users hash to encrypt the nonce and see if it matches the one from the user.
Different applications use different hashing algorithms, which vary greatly in terms of security. When a user creates or changes a password in Active Directory, Windows generates a LAN Manager hash (LM) and a Windows NT hash (NT). The NT hash is encrypted using a custom Windows algorithm, while the LM hash is created using the extremely vulnerable MD4 algorithm.
If a Windows client cannot resolve a hostname using DNS, it will fall back to LLMNR or NBT to attempt to resolve the hostname. LLMNR and NBT will broadcast name resolution requests on their local subnet and will happily forward password hashes to other computers that respond. Pen testing tools like Responder, which is included in Kali Linux, are easy to use and watch for these communications on the network. Even seasoned Windows administrators would be surprised to learn how vulnerable the operating system can be to password interception and other tricks in its default configuration.
Usually, your Windows computer stores two hashes of your password by default, unless you tell it not to. The LM Hash is for backward compatibility to windows systems prior to Windows NT and the NT Hash is for compatibility with Windows 3.1 and later.
Both are old, from Windows 2000 and on most can use NTLMv2 or Kerberos. Believe it or not though many programs still use the LM/NT hashes, so you need to check your network to be sure they are not used before they are shut off.
From online research, I gathered that LM hashes are disabled by default on Windows 10 systems. I also have the Network security: Do not store LAN Manager hash value on next password change Group Policy enabled by default on my VM.
All this points to the fact that there is something wrong (or something I don't understand) about the way pwdump7 retrieves hashdump, and I'm curious about what it is. From the official website, I know that pwdump7 uses the binary SAM and SYSTEM files to retrieve the hashdump.
As pwdump7 is closed source and I wasn't able to find the date of its release, we can't tell for sure, but most probably it was never updated to be able to decrypt this newer encryption scheme, therefore the decrypted data is nonsense. Not only do you get fake LM hashes, but the NTLM hashes also differ from fgdump's output, so they are most probably also the result of wrong decryption and nonsensical.
One remarkable feature of John is that it can autodetect the encryption for common formats. This will save you a lot of time in researching the hash formats and finding the correct tool to crack them.
Load hashes using the Load button. You can either enter the hash manually (Single hash option), import a text file containing hashes you created with pwdump, fgdump or similar third party tools (PWDUMP file option), extract the hashes from the SYSTEM and SAM files (Encrypted SAM option), dump the SAM from the computer ophcrack is running on (Local SAM option) or dump the SAM from a remote computer (Remote SAM option).
Keep in mind that the time needed to crack password hashes with rainbow tables is proportional to the number of hashes loaded. With a brute force attack the cracking time is NOT dependant on the number of unsalted hashes loaded. That's why it's advisable to remove any unnecessary user account with the Delete button.
If you want to crack LM hashes as found on Windows XP by default (the LM Hash column is never empty on the ophcrack main window), first install and enable either the XP free small (if you have less than 512MB of free RAM) or the XP free fast (if you have more than 512MB of free RAM). Do NOT enable both of them since this is generally useless and will slow down the cracking process. Then install and enable the Vista free tables set. Finally install and enable the other XP rainbow tables you may have (XP special, XP german) and Vista one (Vista special). Sort the rainbow tables with the up and down arrows the following way : first the XP free then the Vista free then the XP special after that the Vista special and finally the XP german.
If you want to crack NT hashes as found on Windows Vista by default (the LM Hash column is always empty on the ophcrack main window), first install and enable the Vista free tables set. Then install and enable the Vista special tables set. Disable every other XP tables sets since they are useless and slow down the cracking process. Sort the enabled rainbow tables with the up and down arrows the following way : first the Vista free then the Vista special.
If you want to crack a mix of LM and NT enabled hashes (some accounts have their LM column empty, others have both the LM and NT columns filled with hashes) proceed the same way as "If you want to crack LM enabled hashes".
John the Ripper is a fast password cracker, primarily for cracking Unix (shadow) passwords.Other than Unix-type encrypted passwords it also supports cracking Windows LM hashes and many more with open source contributed patches.
Now lets talk about the password protection method used by Windows. Windows user account passwords are typically stored in SAM hive of the registry (which corresponds to %SystemRoot%\system32\config\SAM file), in the SAM file the password is kept encrypted using the NTLM hash is very well known for its cryptanalysis weaknesses.
The SAM file is further encrypted with the SysKey (Windows 2000 and above) which is stored in %SystemRoot%\system32\config\system file.During the boot-time of Windows the hashes from the SAM file gets decrypted using the SysKey and the hashes are loaded to the registry is then used for authentication purpose. Both system and SAM files are unavailable (i.e, locked by kernel) to standard programs (like regedit) during Windows' runtime .
Where does Windows store these hashes? From my own research, it appears that Windows keeps local user account hashes in the Security Accounts Manager (SAM) database, which is part of the Local Security Authority (LSA). You can read more about these topics in this technet article. 2ff7e9595c
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