Zip files are a collection of files that users frequently come across while everyday internet use. Popular softwares like WinZip are used to zip multiple files into a single file for easy sharing transportation. There are also options to make these files password protected so as to avoid any misuse of data through wrong hands. But as secure as password protection may seem, it is not the case. Most zip softwares use Zip 2.0 encryption format which is known to be have become extremely weak and obsolete with modern computation as they can be cracked within minutes by specialized password recovery tools using a typical Brute-force attack. Therefore you should not reply on this encryption format and rather use AES Encryption.
AES is the new industry standard encryption format that comes in 2 types- 128 bit and 256 bit. 256 bit is more secure as it lets you store a bigger encryption key. Therefore we will focus on 256 bit encryption.
Encrypt zip files with 7-Zip on Windows
Not all softwares support AES encryption but 7-Zip is one famous zip tool that does.
Download 7-Zip here.
Once the software is installed, go to the file or folder that you want to encrypt and right click on it. From the options select 7-Zip –> Add to Achieve
In this window, enter a strong password and select AES-256 under encryption as shown.
Click on Okay and your encrypted zip file is ready to share. Please note that the person with whom you are sharing the zip file would also require a software like 7-Zip to decrypt it.
How to Select a Strong Password
Since 256 encryption is practically impossible to bypass, still the password can be guessed and cracked if proper steps are not followed while choosing it. An ideal password follows these steps –
1. It should be long. Preferably at least about 12-15 characters.
2. It should consist of uppercase, lowercase and special characters along with a combination of numbers.
3. It should not contain any personal details like your name, phone number or address.
4. The password should never be of the typical amateurish kind like 123456, abcdef, abc123 etc.
AES encryption helps to make sure the password is impossible to crack if all these steps are followed while choosing the password. Moreover the specialized password recovery tool would take years of processing to successfully guess such strong passwords. The file will not be of any use to the attacker till then.