WebApp Sec mailing list archives
RE: Re: Encoding Schemes
From: "Lyal Collins" <lyal.collins () key2it com au>
Date: Thu, 10 Nov 2005 10:54:10 +1100
Well, you have some nice bit patterns in these samples, if you think about
the input characters as hex bytes or binary, rather than ascii
E.g.
AAAAAA=C8AFBCD461F1
AAAAAB=C8AFBCD461F2
AAAABB=C8AFBCD462F2
The last character changes by 1 bit for the first 2 samples above, and so
does the output hex
The second last character changed by 1 bitfor the second 2 samples above, so
does the output hex
This leads to the 'key' at position 6 being the common bits of
0x41 xor 0xF1 ('A')
0x42 xor 0xF2 ('B')
So the key byte for pos 6 is something like 'B0'
Rinse and repeat for different byte positions - there are real good bit
changes in most input bytes for the samples shown below
This is assuming nothing like a password length parameter exists in the Xor
for each byte, but that becomes obvious as you look at the results. It
doesn't appear obviously so to me, however.
Lyal
-----Original Message-----
From: cisspstudy () yahoo com [mailto:cisspstudy () yahoo com]
Sent: Thursday, 10 November 2005 7:16 AM
To: webappsec () securityfocus com
Subject: Re: Re: Encoding Schemes
I have some more results for the people on the list:
CLEARTEXT=ENCODED_TEXT
ABCDEF=C8ACBED165F6
BCDEFG=CBADB9D066F7
CDEFGH=CAAAB8D367F8
EFGHIJK=CCA8BADD69FA18
123456=B8DCCEA11586
A23456=C8DCCEA11586
B23456=CBDCCEA11586
AAAAAA=C8AFBCD461F1
AAAAA=C8AFBCD461
AAAA=C8AFBCD4
AAAAAB=C8AFBCD461F2
AAAABB=C8AFBCD462F2
I guess it is a XOR. How do I figure out the key? What is the key?
Cheers
Current thread:
- Encoding Schemes Jason binger (Nov 09)
- Re: Encoding Schemes Rogan Dawes (Nov 09)
- Re: Encoding Schemes Marcus Williams (Nov 09)
- Re: Encoding Schemes ilaiy (Nov 09)
- Re: Encoding Schemes Peter Conrad (Nov 09)
- Re: Encoding Schemes Vasiliy (Nov 09)
- <Possible follow-ups>
- RE: Encoding Schemes David Knapman (Nov 09)
- RE: Encoding Schemes Griffiths, Ian (Nov 09)
- Re: Re: Encoding Schemes cisspstudy (Nov 09)
- RE: Re: Encoding Schemes Lyal Collins (Nov 09)
- Re: Encoding Schemes Haroon Meer (Nov 09)
- Re: Encoding Schemes Byron L. Sonne (Nov 09)
