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Why would you zip and encrypt a file? The best tools and methods for file compression and encryption



If you are creating a Zip file in a folder window using the context menu (right click), you will have the option to encrypt the files and select encryption strength if the Add dialog is displayed. If you choose to add files to an existing Zip file using Add to recently used Zip file there will be no Add dialog and therefore no opportunity to encrypt the files while they are being added. In such a case, you can encrypt files after they have been added.




why would you zip and encrypt a file




Another option would be to use WinZip Express for Explorer. To do this, click Zip and Share (WinZip Express) when you right click. With WinZip Express you can zip, choose to encrypt, and make use of many additional options such as saving to a cloud service.


In each case, WinZip will ask for a password and then encrypt all files currently in the Zip file. Depending on the method you use, you may or may not have the option to change the encryption strength.


If a file in the Zip file is already encrypted, it will first be decrypted and then re-encrypted using the password and encryption method you specified. WinZip will first try to decrypt the file using the current password; if the file cannot be decrypted with this password, WinZip will ask you for the correct password. If you are unable to supply the correct password, the file can be skipped, and it will remain unchanged in the Zip file. The password you entered in the Encrypt dialog box will remain active until either you delete or replace it, or you close the archive.


Compressed files, also known as .zip files, are one of the most convenient ways of transferring data from one computer to another. You can essentially pack gigabytes upon gigabytes of files into a single place, then send it to just about anyone in a single transfer. Because of its great use, many people look to protect their .zip files with a password to ensure only those with permission can unpack the contents.


This guide focuses on showing you how to password protect .zip files on Windows 10, using all the best tools you could possibly need. Ensure that your files are in the right hands by applying a password only you know and only you can share.


Using the Encrypting File System (EFS) encrypts the data of your folder or .zip file and generates a decryption key that acts as a password. Only people with the exact, correct key will be able to decrypt the contents.


WinRAR is an application that allows you to create and manage .zip files, including password protection. The free trial allows you to indefinitely manage your compressed files, and regular updates ensure that your experience is always the best.


One more problem with encrypted ZIP files: No matter which form of encryption you use, anyone with access to the files can see the name of the files within the archive. If the file names provide sensitive information, a thief could take advantage of that. Of course, they would not be able to open any of the files without the password.


Following my answer. If I can list contents of a password-protected ZIP file, check the file types of each stored file and even replace it with another one, without actually knowing the password, then should ZIP files be still treated as secure?


I can hijack (intercept) someone else's file (password-protected ZIP file) and I can replace one of the files it contains, with my one (fake, virus) without knowing the password. Replaced file will remain unencrypted, not password-protected inside the ZIP, but other files won't be modified.


If a victim unpacks a password-protected archive, extracting program will ask for the password only once, not every time per each file. So end user will not see the difference -- whether the program does not ask for a password, because it already knows it (original file) or because the file being extracted doesn't need a password (file modified by me). This way, I can inject something really bad into a password-protected ZIP file, without knowing its password and count on the receiver assuming the file is unmodified.


Confidentiality - marginal at best. Confidentiality is usually rated in terms of how long it will take to gain access to the protected material. I may be able to change the zip file, but as a hacker it'll take me some amount of time either crack the password or brute force it. Not a lot of time, passwords are one of the weaker protections, and given the way zip files are often shared, social engineering one's way to the password is usually not hard.


The trick is - how much better do you want to get? Encrypted email is an option - as a better protection. Although it poses it's own connectivity concerns. And there's many better ways to encrypt data - but the better options also involve key distribution challenges that can add time and cost concerns.


This is one of those cases where security is limited by usability and human intent. The archive manager has no way of telling whether or not the file you modified was meant to be encrypted in the first place. Essentially this is a social engineering attack, in that you tricked the user into believing that the original file was in place. However, the real security vulnerability would be that you had read/write access to a sensitive archive in the first place.


In addition to the risks you have already pointed, IMHO one of the biggest problems with compression tools is related to the use of temporary folders to store the uncompressed files. As the input files can be of arbitrary size, the uncompressed output files might not fit in RAM. A temporary output folder (often the OS's default) is used.


So it does not matter how strong the encryption algorithm is if you forget to properly shred the temporary folders each time you unzip a psw-protected file. Most tools do not automatically clean the output directory nor warn the user about it. Same thing when compressing: you should make sure to shred the original file.


If I were to use the a general definition fo Secure to mean that it enforces Privacy, Authentication, Integrity and Non-Repudiation, I would say its is not secure on a number of counts. But as the password protection on an Encrypted ZIP file intends to only provide Privacy (disallowing the viewing of the content of a file except by intended parties) I would say that it does do its job.


The official .ZIP format specification does allow for hiding the list of file names (but not number of files), as well as hiding metadata such as the original file size and CRC of the original file. But you can't use WinZip or Info-Zip to do that. Additionally, integrity in the official .ZIP specification is provided through the use of one or more digital signatures in addition to the encryption. My personal recommendation, though, is to avoid passwords, and instead use public keys. Key derivation functions are constantly getting faster, and I don't believe any vendor has even tried to keep up.


So the bottom line is, unless there is a vulnerability or back door in the encrypting code, it is as secure as your pass phrase is resistant to brute force attacks. There are various sites on the Internet where you can prototype the scheme you intend to use, to check roughly how long it would take to crack. (Do not use WHAT you intend to use)


Anything anyone can gain physical access to, is crackable, given enough time. However, you can have practical security if the cost and or time required to gain access to the information exceeds its likely value. Unless it is something like financial information, there is often a big difference between what is valuable to a hacker, and what is valuable to you. If the name of your file inside the zip is Attachment_1, and the e-mail's unencrypted contents does not describe the attachment's contents, it doesn't give an hacker much to go on. A hacker is not likely to be willing to spend much time, and certainly not money, to gain access to something that doesn't have a convincingly high probability of containing something of value to him.


Not everything that is password protected can be hacked by brute force attacks. However, zip files can be cracked by brute force. Other systems have checks in place, like for example, lock out after three attempts, passkey verifications etc.


The idea of compressing content into ZIP files has revolutionized the digital workspace. With ZIP files, you can store hundreds of folders and files in a single location, thus making it convenient to transfer and use. Additionally, they save your disk space since it allows compressing of large attachments.


Encryption involves protecting a ZIP file by locking down the archive such that only specific people can view its contents. An encrypted ZIP file has an added layer of protection for confidential information. If you are archiving essential documents or pictures, chances are they contain some content you don't want to expose to the world.


And yes, you can put a strong password on your user account and use Windows security features, but such a move is not adequate since you may leave the computer on by mistake. Besides, someone can still access the files if they use the hard drive on a different computer.


Typically, you use these files when uploading to a site for a particular application or when sending a document to another email. But since email is not secure for sending sensitive documents, encryption allows you to take control over your content's privacy. Encryption, therefore, reduces the chances of access by a third party.


Although Windows 10 does not have password protection for compressed folders and files, you can still take steps to ensure your files are safe. The Encrypting File System (EFS) protects the contents of your ZIP file and provides a decryption key that works like a password. You can only decrypt or open the contents if you have the correct key.


When you encrypt a ZIP file on Windows 10, you add an extra layer of protection. However, the best and proper encryption is through third-party tools. WinZip is a top-notch computer program that provides two kinds of encryption, including AES and ZIP 2.0 (Legacy) encryption. 2ff7e9595c


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