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1. #Remove password protection in excel software
2. #Remove password protection in excel password
3. #Remove password protection in excel crack

#Remove password protection in excel password

However, it has to be noted that all SHA hash algorithms were never designed for password hashing and are thus not considered secure anymore. Office 2013 introduces SHA-512 hashes in the encryption algorithm, making brute-force and rainbow table attacks slower. Passwords of sufficient length and complexity typically cannot be brute-forced. 80% of the files saved in the Office 2007–2010 format. Due to weak passwords, at the moment, cloud computing facilities are capable of unlocking as many as ca. The efficiency of attacks can be considerably enhanced if one of the following means is applied: multiple CPUs (distributed attack), GPGPU (applicable only to Microsoft Office 2007–2010 documents) and cloud computing. Password removal can be done with the help of precomputation tables or a guaranteed decryption attack.Īttacks that target the original password set in Microsoft Excel and Word include dictionary attack, rule-based attack, brute-force attack, mask attack and statistics-based attack. There are a number of attacks that can be employed to find a password or remove password protection from Excel and Word documents. In Excel it is particularly weak, and an equivalent password can easily be found of the form ABABABABABAx where the first 11 chars are either A or B and the last is an ASCII character.

#Remove password protection in excel software

The protection for worksheets and macros is necessarily weaker than that for the entire workbook as the software itself must be able to display or use them. Office 2016 (Access, Excel, OneNote, PowerPoint, Project, and Word) uses 256-bit AES, the SHA-1 hash algorithm, and CBC ( Cipher Block Chaining) by default. Office 2013 (Access, Excel, OneNote, PowerPoint, Project, and Word)uses 128-bit AES, again with hash algorithm SHA-1 by default.

#Remove password protection in excel crack

With the help of the SHA-1 hash function, the password is stretched into a 128-bit key 50,000 times before opening the document as a result, the time required to crack it is vastly increased.Įxcel and Word 2010 still employ AES and a 128-bit key, but the number of SHA-1 conversions has doubled to 100,000 further increasing the time required to crack the password. At present there is no software that can break this encryption. In Office 2007 (Word, Excel and PowerPoint), protection was significantly enhanced since a modern protection algorithm named Advanced Encryption Standard was used. Weak passwords can still be recovered quickly even if a custom CSP is on. Choosing a non-standard Cryptographic Service Provider allows increasing the key length. The default protection in Office XP and 2003 was not changed, but an opportunity to use a custom protection algorithm was added. This protection algorithm is also currently considered to be weak and presents no difficulties to hacking software.

In Excel and Word the key length was increased to 40 bits. Hacking software is now readily available to find a 16-bit key and decrypt the password-protected document instantly.

In Excel and Word 95 and prior editions a weak protection algorithm is used that converts a password to a 16-bit key. History of Microsoft Encryption password To provide improved security, Microsoft has been consistently enhancing the Office encryption algorithm strength. Due to the encryption of a document protected by a password to open it, a hacker needs to decrypt the document to get access to its contents. If a user fails to enter a correct password to the field which appears after an attempt to open a password-protected document, viewing and editing the document will not be possible. It is possible to set this type of password in all Microsoft Office applications. The password that encrypts a document also restricts the user from opening the document.