Using cracked RC4 key to read a PDF
#1
Tongue 
I recently wanted crack an old PDF to see what was inside, so I searched around a bit and found out I could crack RC4 encrypted PDFs very quickly. After cracking the key I tried both writing a Python script to decrypt the streams inside the PDF using PyPDF2 and decrypting some streams by hand but PyPDF2 returned an error and my manual tries yielded invalid results.

Am I doing something wrong? How would I use this key to decrypt the PDF file?
Both an owner and user password is set btw

Code:
Session..........: hashpdftests Status...........: Cracked Hash.Mode........: 10410 (PDF 1.1 - 1.3 (Acrobat 2 - 4), collider #1) Hash.Target......: $pdf$1*2*40*-28*1*16*xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx...f9157c Time.Started.....: Fri Jul 21 08:26:22 2023, (47 mins, 55 secs) Time.Estimated...: Fri Jul 21 09:14:17 2023, (0 secs) Kernel.Feature...: Optimized Kernel Guess.Mask.......: ?b?b?b?b?b [5] Guess.Queue......: 1/1 (100.00%) Speed.#1.........:  293.3 MH/s (105.93ms) @ Accel:256 Loops:128 Thr:32 Vec:1 Recovered........: 1/1 (100.00%) Digests (total), 1/1 (100.00%) Digests (new) Progress.........: 840475607040/1099511627776 (76.44%) Rejected.........: 0/840475607040 (0.00%) Candidate.Engine.: Device Generator Candidates.#1....: $HEX[c8611bacc3] -> $HEX[ffff3faec0]
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Messages In This Thread
Using cracked RC4 key to read a PDF - by nullptr - 07-21-2023, 09:59 PM