Mode of Operation
Attackers will use a variety of methods to create a functioning codebook. The most common technique, however, is to use an automated system that can generate large amounts of random data, which is then used to create thousands of different encryption algorithms. This process can be extremely time-consuming depending on the size of the file that is being encrypted. For example, if the attacker has stolen a company’s encryption key for their file server and has access to 10 GB of sensitive data, it could take months for them to collect enough random numbers to encrypt all 10 GB using a codebook attack.
What is Codebook Attack?
The codebook attack is a very common password hacking technique where the hacker guesses the passwords of a user by using common phrases and words as password phrases. Hackers always use this method when a dictionary attack has not been able to retrieve any meaningful results. Codebooks are usually data stored in files on the web server, which contain nothing but common words used as passwords by users. The most popular codebook is a list of passwords that can be recovered through John The Ripper software utility. At some point, someone will start to suspect that they have been the target of a codebook attack. This is when a hacker has exfiltrated sensitive data, often in the form of an encrypted file, and is holding it for ransom in exchange for money. In order to decrypt this file, an individual must send them $USD or another cryptocurrency. The best way to protect against a codebook attack is not by paying them off but by researching and implementing stronger encryption practices at your company. The longer an attacker has had access to your system and data, the greater the chance that they are able to compromise it further.