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The ZIP file format is a data compression and archive format. A ZIP file contains one or more files that have been compressed, to reduce file size, or stored as is. The ZIP file format permits a number of compression algorithms.
Compression methods
The .ZIP File Format Specification documents the following compression methods: stored (no compression), Shrunk, Reduced (methods 1-4), Imploded, Tokenizing, Deflated, Deflate64, bzip2, LZMA (EFS), WavPack, PPMd. The most commonly used compression method is DEFLATE, which is described in IETF RFC 1951.
Compression methods mentioned, but not documented in detail in the specification include: PKWARE Data Compression Library (DCL) Imploding (old IBM TERSE), IBM TERSE (new), IBM LZ77 z Architecture (PFS). Encryption
Zip supports a simple password-based symmetric encryption system which is documented in the zip specification, and known to be seriously flawed. In particular it is vulnerable to known-plaintext attacks which are in some cases made worse by poor implementations of random number generators. Our remove password service can recover the file by this type of attack.
New features including new compression and encryption (e.g. AES) methods have been documented in the .ZIP File Format Specification since version 5.2. A WinZip-developed AES-based standard is used also by 7-Zip, XCeed, and DotNetZip, but some vendors use other formats. PKWARE SecureZIP also supports RC2, RC4, DES, Triple DES encryption methods, Digital Certificate-based encryption and authentication (X.509), and archive header encryption. Our remove password service can also recover the file by this type of attack (with any encryption type).
File name encryption is introduced in .ZIP File Format Specification 6.2, which encrypts metadata stored in Central Directory portion of an archive, but Local Header sections remain unencrypted. A compliant archiver can falsify the Local Header data when using Central Directory Encryption. As of Version 6.2 of the specification, the Compression Method and Compressed Size fields within Local Header are not yet masked.
AES encryption: AES is the Advanced Encryption Standard, which is the result of a three-year competition sponsored by the U.S. Government's National Institute of Standards (NIST). This encryption method, also known as Rijndael, has been adopted by NIST as a Federal Information Processing Standard. We can remove or recover password from AES encrypted files (128 bits or 256bits formats).
WinZip supports AES encryption in two different strengths: 128-bit AES and 256-bit AES. These numbers refer to the size of the encryption keys that are used to encrypt the data. 256-bit AES is stronger than 128-bit AES, but both of them can provide significantly greater security than the standard Zip 2.0 method described below. An advantage of 128-bit AES is that it is slightly faster than 256-bit AES, that is, it takes less time to encrypt or decrypt a file. The security of your data depends not only on the strength of the encryption method but also on the strength of your password, including factors such as length and composition of the password, and the measures you take to ensure that your password is not disclosed to unauthorized third parties.
The Zip file format extension used by WinZip to store AES-encrypted files is not supported by versions of WinZip prior to 9.0 and is not yet supported by some other Zip file utilities.
Legacy (Zip 2.0) encryption: this older encryption technique provides a measure of protection against casual users who do not have the password and are trying to determine the contents of the files. However, the Zip 2.0 encryption format is known to be relatively weak and cannot be expected to provide protection from individuals with access to specialized password recovery tools.
You should not rely on Zip 2.0 encryption to provide strong security for your data. If you have important security requirements for your data, you should instead consider using WinZip's AES encryption, described above. Zip password recovery online decryption service takes place on our servers, so there is no need to install additional software.
The only advantage of Zip 2.0 encryption over the more secure AES encryption is that it is supported by most Zip file utilities, including earlier versions of WinZip. Files that you encrypt using this technique can be extracted by anyone who knows the correct password and has access to almost any Zip file utility. Additionally, Zip 2.0 encryption is supported by WinZip Self-Extractor 2.2 and later and by WinZip Self-Extractor Personal Edition (included in WinZip 9.0 and later); the AES encryption method described above is only supported by WinZip Self-Extractor 3.0 and later.
There are many software programs available on the internet that can attempt to remove 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 removal or 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 remove password zip online service below: