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NTLM password cracking
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OK, so I have an interest in cracking passwords. Nothing illegal, I assure you, mostly just a recreational thing. (I have actually helped friends and family on numerous occasions to recover lost photo albums from old computers that they had forgotten the passwords to.)

Now, I have managed to lock myself out of one of my windows computers. I tried using ophcrack with all free tables, but the password was not found. Fortunately for me, just a few days before, I had finished building several rainbow tables for rainbowcrack of various sizes, totaling a bit over 10 Gb worth of tables. I copied the hash detected by ophcrack from the encrypted SAM file into rainbow crack (gui version because the linux version did not work on linux for some reason and windows command line is terrible) and then loaded the tables. of the 6 tables that I had finished, only 2 of them actually worked. These were the 2 smallest, using only default pass length and # of keys. (these were generated with the program winrtgen, NOT with the included command line table generator with rainbow crack, again because of windows command line) on 3 of the other 4 tables that did not work, it gave the message "table length incorrect". On the 4th table, it said that there was no hash algorithm for "lm" or something like that.

After doing some searching, I found absolutely no mention of the "table length incorrect" issue, nor the missing algo.


>> tl;dr:

>>1) what does "table length incorrect" in rainbow crack mean, and how do I fix it?

>>2) since I know the specific hash I am trying to reverse, is there a way that I can try to just brute force that one SPECIFIC hash? I know that the idea is that the algo is MUCH harder to reverse than it is to run in the first place, but it should be possible to do so, right? if so, how do I go about doing this?

Does /g/ use rainbow tables? general pass cracking thread.

pic semi related.
>>
>>52632120
>1) what does "table length incorrect" in rainbow crack mean, and how do I fix it?

It means it is not formatted correct for rainbow crack

>2) since I know the specific hash I am trying to reverse, is there a way that I can try to just brute force that one SPECIFIC hash? I know that the idea is that the algo is MUCH harder to reverse than it is to run in the first place, but it should be possible to do so, right? if so, how do I go about doing this?

well that is what a rainbow table is for so you can just look up the hash and find the password. if you are asking can you do somthing like SHA1 in reverse to create data from the hash then no

just do an NT password reset ffs
>>
Also, do you think there could be a market for an online password recovery service? it would work like this:

1) customer contacts service provider with a hash that they need to find the plaintext for. If they do not know how to do this, the service provider will walk them through the steps to do so.

2. service provider manually inputs the hash into rainbow crack and/or ophcrack and cracks the password using a combination of free tables and home made tables.

3. if the password is found, the service provider contacts customer and tells them that it was found. If the password is not found, service provider contacts customer and informs them that it was not found.

>> up to this point, there has been NO transfer of money.

4. The service provider will now provide the password plaintext if payment is received.

(the only issue with this is that of trust. How does the customer know they will get a plaintext that works before paying money, or how does the service provider know they will be paid if they provide the plaintext first?)
>>
>>52632252
>>> up to this point, there has been NO transfer of money.
>4. The service provider will now provide the password plaintext if payment is received.

Well that really depends on how much computational resources are used. What if it has taken 900 centuries like my password would take to crack? who is gonna pay the bill? it is gonna be trillions of dollars senpai
>>
>>52632185

>>It means it is not formatted correct for rainbow crack

How do I fix this? the program used said that it is compatible, and 2 tables created work fine. All the tables I made are in the .rt format, not .rtc Is this the problem? (the ones that give this error are several Gb each, and I did not use the rt2rtc.exe thing on them. could doing so fix the problem?)

Also, from what you are saying, creating a rainbow table does not actually reverse any hash, it just hashes a TON of plaintexts and then when cracking, the computer compares these hashes to the one it is looking for and then when it finds a match it then looks to see what plaintext generated that hash, right? in other words, you cant reverse the ntlm algo.

>>just do an NT password reset ffs

Is this the thing where you essentially delete the password instead of actually trying to crack it?

Thanks
>>
>>52632343
The service provider is always building new tables, which does take resources, but the actual cracking of the password is done with the completed tables. That means that IF the password is found, it will take a very small amount of computational power and time to do so because all the work was done up front with the table construction. Not planning on running a server farm or anything to build tables, just have one or two computers building them in the background over time.
>>
>>52632120
Give it back Jamal
>>
>>52632388
rainbow tables are close to useless for what you want though as the passwords will have been hashed with a salt anyway.
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