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Portable Document Format (PDF) is an open standard for document exchange. This file format created by Adobe Systems in 1993 is used for representing documents in a manner independent of application software, hardware, and operating systems. Each PDF file encapsulates a complete description of a fixed-layout flat document, including the text, fonts, graphics, and other information needed to display it.
In 1991 Adobe Systems co-founder John Warnock outlined a system called "Camelot" that evolved into the Portable Document Format (PDF).
A PDF file may be encrypted for security, or digitally signed for authentication.
The standard security provided by Acrobat PDF consists of two different methods and two different passwords, "user password" and "owner password". A PDF document may be protected by password to open ('user' password) and the document may also specify operations that should be restricted even when the document is decrypted: printing, copying text and graphics out of the document, modifying the document, or adding or modifying text notes and AcroForm fields (using 'owner' password). However, all operations (except the document open password protection, if applicable) which are restricted by "owner" or "user" passwords are trivially circumvented by many commonly available "PDF cracking" software and even freely online, and if circumvented these restrictions no longer let the author control what can and cannot be done with the pdf file once distributed. This warning is also displayed when applying such restrictions using Adobe Acrobat software to create or edit PDF files. PDF password recovery online decryption service takes place on our servers, so there is no need to install additional software.
There are many software programs available on the internet that can attempt to recover the password, but that can take weeks, months or even years if it's a lengthy password or it uses special characters like: $,%,& etc. In addition to the relatively high costs of these software programs (usually tens of euros/dollars), these do not guarantee a fast password recovery in a reasonable amount of time. At a mere fraction of the price of those software programs, and in a few hours, you can obtain your encrypted file using our PDF password recovery online service below:
A PDF file may be encrypted for security, or digitally signed for authentication.
The standard security provided by Acrobat PDF consists of two different methods and two different passwords, user password, which encrypts the file and prevents opening, and owner password, which specifies operations that should be restricted even when the document is decrypted, which can include: printing, copying text and graphics out of the document, modifying the document, or adding or modifying text notes and AcroForm fields. The user password (controls opening) encrypts the file and requires password cracking to defeat, with difficulty depending on password strength and encryption method - it is potentially very secure (assuming good password and encryption method without known attacks). The owner password (controls operations) does not encrypt the file, and instead relies on client software to respect these restrictions, and is not secure. An "owner password" can be removed by many commonly available "PDF cracking" software, including some free online services.[52] Thus, the use restrictions that a document author places on a PDF document are not secure, and cannot be assured once the file is distributed; this warning is displayed when applying such restrictions using Adobe Acrobat software to create or edit PDF files.
Even without removing the password, most freeware or open source PDF readers ignore the permission "protections" and allow the user to print or make copy of excerpts of the text as if the document were not limited by password protection.
Some solutions, like Adobe's LiveCycle Rights Management, are more robust means of information rights management, which can both restrict who can open documents, but also reliably enforce permissions in ways that the standard security handler does not.
Usage rights
Beginning with PDF 1.5, Usage rights (UR) signatures are used to enable additional interactive features that are not available by default in a particular PDF viewer application. The signature is used to validate that the permissions have been granted by a bonafide granting authority. For example, it can be used to allow a user:
For example, Adobe Systems grants permissions to enable additional features in Adobe Reader, using public-key cryptography. Adobe Reader verifys that the signature uses a certificate from an Adobe-authorized certificate authority. The PDF 1.5 specification declares that other PDF viewer applications are free to use this same mechanism for their own purposes.