This article aims showing what PDF passwords can be or can not be removed during removing PDF passwords with restrictions with VeryDOC PDF Password Remover.
Like you can tell, VeryDOC PDF Password Remover supports instantly removing PDF owner passwords with restrictions, as well as open passwords known by users previous. However, not any kinds of encrypted PDF passwords could be supported to remove, as well as specified PDF files. So, in the following paragraphs, what can be of removing or not by this tool would be shown in the following description:
What VeryDOC PDF Password Remover support based on PDF type and encryption modes:
- For PDF type - support up to PDF version 1.8, including Acrobat 9.0 PDF files
- For encryption level - remove 40 bits and 128 bits RC4 encryption owner passwords
- For encryption mode – 128 bits AES - remove AES encryption owner passwords
What VeryDOC PDF Password Remover does not support:
- PDF files which are not what software itself supports
- PDF passwords set without what I mentioned in supported encryption modes
- PDF passwords encrypted beyond mainstream encryption of PDF
- PDF passwords encrypted with specific Adobe Plug-ins
- PDF passwords which are set by not Adobe Corporation
By now, maybe you need to experience this tool, so, it is easy for you to try VeryDOC PDF Password Remover here. And then, you wonder what encryption modes Adobe Corporation have designed for us, then, please read the following extension knowledge:
Basically, three main ways can be used to encrypt a PDF file by Adobe Corporation:
- Password encryption
Password encryption is a technology, which depends on a shared password by publisher and recipients. If you do not understand this, here is an example:
Suppose the publisher use a string like “No1Kn0w$” to encrypt PDF, and then, the recipients need to use the same string to decrypt it. However, to prevent this encryption from being attacked by brute force, as well as guessing of simple passwords, please make sure complex passwords, e.g., like song lyrics, poetry, and other long phrases as source material of PDF passwords to set.
- Public Key Infrastructure (PKI) encryption
PKI encryption, which is a further technology, help you set greater protection by using additional cryptography and digital certificates.
For instance, while encrypting, the publisher’s computer randomly generates a symmetric key(up to AES256), and encrypts that key to each recipient’s asymmetric public key to include in the document with the symmetric key encrypted content. In return, the recipient computer uses their own private key to decrypt the symmetric key, and then decrypt the document. When the private key is stored on a token, e.g. USB, etc., it can provide two factor security, which are requiring the token and any PIN codes to unlock this token.
- Rights Management
Rights Management, which has been developed to provide integration into enterprise authentication (AuthN) and authorization (AuthZ) infrastructure without requiring PKI, could be used in those same directories to read in groups of users.
With this technology, rights management “policy”, which is an easily reusable way to protect documents, can be created by administrators. In this kind of policy, how to open the document, what you can do with the document and what can be tracked based on what users have done with the document, can be set professionally and easily as you wish. The publisher then selects the policy to protect a document. In addition to username/password types of authentication, the server can also support Kerberos single sign on (SSO),PKI authentication (which is different than PKI encryption above), OTP, and other custom methods. With the professional help of this technology, document usage can be expired, revoked, version controlled, watermarked, and audited. Thus, it is great to use this brilliant technology for communities of users. In addition, this technology can be compatible with popular smart phones and tablet devices.
At last, what are important is that, three encryption methods mentioned above, are all possible to restrict printing, clipboard, and modification as usual.
In the end, welcome to share your problems and questions with comments here, if you encounter them during removing PDF passwords with VeryDOC PDF Password Remover.