[Samba] Being able to read password hashes

Achim Gottinger achim at ag-web.biz
Wed Jul 23 03:59:15 MDT 2014 

Am 23.07.2014 11:43, schrieb Rowland Penny:
> On 23/07/14 10:31, Achim Gottinger wrote:
>> Am 22.07.2014 21:52, schrieb Stuart Naylor:
>>> Think it was mentioned here. 
>>> http://technet.microsoft.com/en-us/magazine/ff848710.aspx
>>>
>>> Apols guys as I was just trying to work out the implications.
>>>
>>> Makes it easier for the admin to be honest, the admin might not know 
>>> the password but you can set up users with the password they know.
>>>
>>>     -----Original message-----
>>>> From:Jefferson Davis <jdavis at standard.k12.ca.us>
>>>> Sent: Tuesday 22nd July 2014 18:08
>>>> To: Stuart Naylor <stuartiannaylor at thursbygarden.org>
>>>> Cc: samba at lists.samba.org
>>>> Subject: Re: [Samba] Being able to read password hashes
>>>>
>>>> So, how do you do this?
>>>>
>>>> ----- Original Message -----
>>>>
>>>> From: "Stuart Naylor" <stuartiannaylor at thursbygarden.org>
>>>> To: "Achim Gottinger" <achim at ag-web.biz>, samba at lists.samba.org
>>>> Sent: Tuesday, July 22, 2014 12:56:57 AM
>>>> Subject: Re: [Samba] Being able to read password hashes
>>>>
>>>> I just wondered that is all.
>>>>
>>>> On a M$ AD you can only write not read the hash directly.
>>>>
>>>> Its different on samba4 and thought I would just mention it.
>>>>
>>>>
>>>>
>>>>
>>>>
>>>> -----Original message-----
>>>>> From:Achim Gottinger <achim at ag-web.biz>
>>>>> Sent: Monday 21st July 2014 18:38
>>>>> To: samba at lists.samba.org
>>>>> Subject: Re: [Samba] Being able to read password hashes
>>>>>
>>>>> Am 21.07.2014 19:03, schrieb Jefferson Davis:
>>>>>> I was wondering about this as we continue our migration.
>>>>>>
>>>>>> I have a script that my tech's use to temporarily change 
>>>>>> passwords so that they can login as a user for testing config 
>>>>>> changes, repairs, etc.
>>>>>>
>>>>>> While I'm still a bit bent about having to rework my entire 
>>>>>> freaking account mgmt toolchain due to the massive changes 
>>>>>> wrought by AD DC functionality in samba4, it's nice to know the 
>>>>>> functionality we need is there.
>>>>>>
>>>>>> Now to see if I can locate a reasonably-priced time-travel device 
>>>>>> on craigslist to allow the extra time needed to do this...
>>>>>>
>>>>>> ----- Original Message -----
>>>>>>
>>>>>> From: "Stuart Naylor" <stuartiannaylor at thursbygarden.org>
>>>>>> To: "Rowland Penny" <rowlandpenny at googlemail.com>, "sambalist" 
>>>>>> <samba at lists.samba.org>
>>>>>> Sent: Monday, July 21, 2014 9:21:33 AM
>>>>>> Subject: Re: [Samba] Being able to read password hashes
>>>>>>
>>>>>> With any Microsoft active directory server you can not get access 
>>>>>> to read password hashes you can only change them.
>>>>>>
>>>>>> Its the fact I can get the hash so easily and also ever-body else's.
>>>>>>
>>>>>> I am not all that bothered as for this sysadmin its a Brucie Bonus.
>>>>>>
>>>>>> Irrespective of the website if its not there all I need to do is 
>>>>>> throw some cuda cores at http://hashcat.net/hashcat/ and one way 
>>>>>> or another I will get it.
>>>>>>
>>>>>> Should the hashes be so easily available was my main question?
>>>>>>
>>>>>> I was just wondering what others thought, seems cool enough.
>>>>>>
>>>>>> Stuart
>>>>>>
>>>>>>
>>>>>> -----Original message-----
>>>>>>> From:Rowland Penny <rowlandpenny at googlemail.com>
>>>>>>> Sent: Monday 21st July 2014 10:24
>>>>>>> To: sambalist <samba at lists.samba.org>
>>>>>>> Subject: Re: [Samba] Being able to read password hashes
>>>>>>>
>>>>>>> On 21/07/14 10:02, Philippe.Simonet at swisscom.com wrote:
>>>>>>>> not cracking : ntlm hash database lookup.
>>>>>>> Same difference, the OP said he put a unicodePwd password into a 
>>>>>>> webpage
>>>>>>> that deals with NTLM passwords and got his plain password back, 
>>>>>>> or are
>>>>>>> you missing the point?
>>>>>>>
>>>>>>> Rowland
>>>>>>>>> -----Original Message-----
>>>>>>>>> From: samba-bounces at lists.samba.org [mailto:samba-
>>>>>>>>> bounces at lists.samba.org] On Behalf Of Rowland Penny
>>>>>>>>> Sent: Monday, July 21, 2014 10:46 AM
>>>>>>>>> To: samba at lists.samba.org
>>>>>>>>> Subject: Re: [Samba] Being able to read password hashes
>>>>>>>>>
>>>>>>>>> On 21/07/14 09:29, Stuart Naylor wrote:
>>>>>>>>>> ldbsearch -H /var/lib/samba/private/sam.ldb
>>>>>>>>> '(&(objectclass=person)(name=Administrator))' name unicodePwd
>>>>>>>>>> # record 1
>>>>>>>>>> dn: CN=Administrator,CN=Users,DC=office,DC=zentyal,DC=lan
>>>>>>>>>> name: Administrator
>>>>>>>>>> unicodePwd:: kXh1DQFudwnw+lnHhubyUw==
>>>>>>>>>>
>>>>>>>>>> http://www.hashkiller.co.uk/ntlm-decrypter.aspx just took 
>>>>>>>>>> 242ms to return
>>>>>>>>> my password
>>>>>>>>> Are you sure? you put a unicodePwd into something that cracks 
>>>>>>>>> ntlm
>>>>>>>>> passwords and got your plain password back??
>>>>>>>>>
>>>>>>>>> Rowland
>>>>>>>>>
>>>>>>>>>> Only zent1 as its just a VM running a test of Zentyal3.5
>>>>>>>>> -- 
>>>>>>>>> To unsubscribe from this list go to the following URL and read 
>>>>>>>>> the
>>>>>>>>> instructions: https://lists.samba.org/mailman/options/samba
>>>>>>>
>>>>> After reading this
>>>>> http://technet.microsoft.com/de-de/magazine/ff848710.aspx the 
>>>>> unicodePwd
>>>>> is not encrypted and it does not look too difficulta to create the
>>>>> plaintext password out of this base64 sequence.
>>>>>
>>>>> That article also mentiones that this unicodePwd attribute only 
>>>>> exists
>>>>> on servers having ad lds templates applied whom seem to be not
>>>>> neccessary for normal ad behaviour.
>>>>>
>>>>>
>>>>>
>>>>>
>>>> -- 
>>>> To unsubscribe from this list go to the following URL and read the
>>>> instructions: https://lists.samba.org/mailman/options/samba
>>>>
>>>>
>>>>
>>>> -- 
>>>>
>>>>
>>>>
>>>> Jefferson K Davis
>>>> Technology and Information Systems Manager
>>>> Standard School District
>>>> 1200 North Chester Ave
>>>> Bakersfield, CA 93308
>>>> 661.392.2110 ext 120 (office)
>>>> http://district.standard.k12.ca.us
>>>>
>>>> District Users: Click here to report technology issues
>>>>
>>>>
>>>>
>>>>
>> To change the password with an hash (read earlier from unicodePwd) i 
>> assume you must modify dBCSPwd 
>> http://msdn.microsoft.com/en-us/library/cc245687.aspx and maybe 
>> unicodePwd as well. A few other erquirements are mentioned in the link.
>>
>> Tried mimikaze.exe and it's scary how fast it displays all user 
>> passwords in cleartext.
>>
>> Interesting thread.
>>
>> achim~
>>
> Hi, yes you need to encode the password, you can do this in bash like 
> this:
>
> echo -n "\"PASSWORD\"" | iconv -f UTF-8 -t UTF-16LE | base64 -w 0
>
> and then put the result into the users 'unicodePwd' attribute.
>
> You are supposed to have to do this over SSL, but I seem to be able to 
> this without using SSL.
>
> Rowland
Hi Rowland,

The aim is to be able to change an user password temporary for 
maintainence purpose and then restoring it without knowing it.

The encrypted base64 encoded password can be read as described earlier. 
Now the question is what has do be done to restore it.

Writing to "unicodePwd" requires the knowledge of the unencrypted password.

Cheers,
achim~

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