option for pure number as password

Henning Noren — Wed, 12 May 2021 00:51:58 -0000

Dear Eberhard,

As far as I am aware, there is no significant speedup that can be made based on specific character-group-modes (such as all numbers). There is really nothing special about numbers or characters when in comes to the password for a PDF and precomputing for common groups is not feasible due to various factors that always are unique for the PDF (such as document ID).

The solution you suggested of limiting the character set and length is the correct one for these cases.

Kind Regards,
Henning

Password recovery fails using word list

J SJ — Sat, 16 Jun 2018 05:08:37 -0000

it's user password, there are sites that can crack owner passwords online. anyway, I tried both -o and -u. same result.

Password recovery fails using word list

J SJ — Sun, 03 Jun 2018 07:01:52 -0000

I have the same problem. There is not much instructions for this.

Password recovery fails using word list

bulkomorowski — Sun, 27 Nov 2016 10:56:24 -0000

checki if this is a user or owner password

Patterns, Multi-core, User and Owner Paswords

Stefan — Thu, 28 Jul 2016 06:11:49 -0000

Hi, this is great. I'm trying to find a password on an old Dell with 4x Xeon processors and will benefit immensely from the multi cpu support.

However, as per your notes only the pattern search benefits from the multi core support but I can't for the life of me formulate a pattern which simply mimics the regular "random with increasing character number". Is that something you can help me with?

Multi-core and multi-computer extension v0.11

Shreepad S — Sun, 29 Nov 2015 06:54:01 -0000

Pls see this: https://github.com/shreepads/pdfcrack-mp

It can do all the user/ owner passwords and supports multi-core patterns.

You can now run something like this test in the Makefile:

./pdfcrack -t 4 -e "[:upper:]{1,2}[:lower:]{2,3}[:digit:][:punct:]" ./testpdfs/TestPDF7.pdf

This will use 4 threads of execution in parallel to find a password that

Starts with an uppercase letter
Followed by 1 to 2 lower case letters
Followed by 2 to 3 digits
And one punctuation mark

Patterns, Multi-core, User and Owner Paswords

Shreepad S — Sun, 22 Nov 2015 17:44:46 -0000

Am pretty much done with the patterns related work. It now supports regex like character classes with support for ranges of repitition for each (in addition to the basic list of chars patterns).

You can now run something like this test in the Makefile:

./pdfcrack -t 4 -e "[:upper:]{1,2}[:lower:]{2,3}[:digit:][:punct:]" ./testpdfs/TestPDF7.pdf

This will use 4 threads of execution in parallel to find a password that
Starts with an uppercase letter
Followed by 1 to 2 lower case letters
Followed by 2 to 3 digits
And one punctuation mark

Next up, am planning to add a character class [:word:] which will include words from a wordlist so you can have a pattern like this

{4,8}[:word:]{2,3}[:digit:][:punct:]

Word is going to be special
It can only appear once
The leading range {4,8} indicates that it should use words from the wordlist that are at least 4 chars and if longer than 8 chars truncate to 8 chars

Still need a test PDF file for the new PDF security revision 6...

Multithreading

Shreepad S — Sat, 26 Sep 2015 18:13:09 -0000

Pls see https://github.com/shreepads/pdfcrack-mp

Patterns, Multi-core, User and Owner Paswords

Shreepad S — Sat, 26 Sep 2015 18:11:04 -0000

Thanks! That seems useful... Now to find someone who can give me a test doc!

Patterns, Multi-core, User and Owner Paswords

Henning Noren — Sat, 26 Sep 2015 10:19:02 -0000

Check out this page though for someone who claims to have reversed engineered it with a pseudo code implementation:
http://esec-lab.sogeti.com/posts/2011/09/14/the-undocumented-password-validation-algorithm-of-adobe-reader-x.html

I have not looked into it though.

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option for pure number as password

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