PDFCrack is the best free PDF password recovery tool available, assuming that's what you're after - an actual password "recovery" and not a simple PDF password removal or reset.
Method: PDFCrack would be considered a true PDF password recovery program since it recovers both the user password and owner password from encrypted PDFs. PDFCrack uses a brute-force password recovery method.
Limits: PDFCrack works with PDF files up to version 1.6 with 128-bit RC4 encryption.
My Test: PDFCrack recovered the 4-digit owner password on a version 1.6 PDF file with 128-bit RC4 encryption in two minutes. A longer and/or more complicated PDF password could take days, weeks, or even longer to recover.
If all you need is a way to bypass the permissions security in a PDF then PDFCrack is probably more than you need in a PDF password cracker. However, if you need to know the actual owner or user password, PDFCrack is your best bet.
PDFCrack is a command-line tool and should work on Windows 7, Windows Vista, and Windows XP, including both 32-bit and 64-bit versions.
Limits: PDFCrack works with PDF files up to version 1.6 with 128-bit RC4 encryption.
My Test: PDFCrack recovered the 4-digit owner password on a version 1.6 PDF file with 128-bit RC4 encryption in two minutes. A longer and/or more complicated PDF password could take days, weeks, or even longer to recover.
If all you need is a way to bypass the permissions security in a PDF then PDFCrack is probably more than you need in a PDF password cracker. However, if you need to know the actual owner or user password, PDFCrack is your best bet.
PDFCrack is a command-line tool and should work on Windows 7, Windows Vista, and Windows XP, including both 32-bit and 64-bit versions.