ada 2 proteksi pass:
1. User Pass: utk read/buka PDF
2. Permissions/ Owner Pass: utk modif/edit/print/ copy isi.

kebanyakan program decrypt cuma support remove OWNER pass,
di antaranya yang pernah gw tes:
- 3A PDF Password Remover
http://www.aaapdf. com/pdfdec/ pdf-password- remover.html
- Adult PDF Password Recovery (remover)
http://www.adultpdf .com/products/ pwdremover/ index.html
- Elcomsoft/Dmitry Sklyarov's Advanced E-Book Processor 2.2
http://www.cs. cmu.edu/~ dst/Adobe/ Gallery/
- Guaranteed PDF (GuaPDF) Decrypter-Restricti ons Remover
http://www.password -crackers. com/service. html

sedangkan yang bisa recover USER pass:
- Elcomsoft Advanced PDF Password Recovery Pro
http://www.elcomsof t.com/apdfpr. html
http://www.crackpas sword.com/ products/ prs/othersoft/ pdf/
- PDF Password Cracker Pro
http://crackpdf. com/index. html

utk OWNER pass sih gampang.. cuma tinggal di-remove doang
pake program remover di atas, gak perlu scanning.

gw tes bikin PDF pake Adobe Acrobat 3D/Pro
trus dikasih user & owner pass.

utk USER pass cuma bisa pake metoda brute-force / dictionary
kek RAR/ZIP Pass recovery.
pake PDF Password Cracker Pro 2.0 jelek.
gw kan udah tau pass, trus gw set min-max karakternya,
masa pass-nya gak ketemu juga.
pake APDFPR Pro baru oke..!

trus kalo user pass-nya blom tau, brp lama brute force-nya?
ya.. sama lamanya ma brute force ZIP/RAR :D
bisa sehari, bisa juga mingguan krn bisa di pause|resume.
tes dulu aja dgn dictionary attack berdasarkan kata² olahan sendiri.

ada catatan kecil:
di help-nya produk Elcomsoft suka nyantumin bahwa produknya
akan lebih optimal (scan cepet) menggunakan prosesor Intel.