Cryptography Attacks: 6 Types & Prevention

Cryptography is a mechanism to ensure data security in transit or at rest. Organizations are investing heavily in encryption solutions to protect their data with the rise in cybersecurity breaches. However, hackers, too, are proving equal to the task by evolving advanced techniques to target cryptographic solutions. 

What is cryptography?

Cryptography is a security mechanism for storing and transmitting sensitive data such that only the sender and the intended receiver can read or understand it. Key(s) are used to encode (at the sender's end) and decode (at the receiver's end) the data. Encryption is the process of converting plaintext or data into ciphertext or encoded data (that is not readable to everyone). Converting the ciphertext or encrypted data to a readable form or decoded version is called decryption.

What are cryptography attacks?

A cryptographic attack is a method used by hackers to target cryptographic solutions like ciphertext, encryption keys, etc. These attacks aim to retrieve the plaintext from the ciphertext or decode the encrypted data. Hackers may attempt to bypass the security of a cryptographic system by discovering weaknesses and flaws in cryptography techniques, cryptographic protocol, encryption algorithms, or key management strategy.

Passive and active attacks

A cryptography attack can be either passive or active.

• Passive attacks:

  Passive cryptography attacks intend to obtain unauthorized access to sensitive data or information by intercepting or eavesdropping on general communication. In this situation, the data and the communication remain intact and are not tampered with. The attacker only gains access to the data.

• Active attacks: On the other hand, active cryptography attacks

  involve some kind of modification of the data or communication. In this case, the attacker not only gains access to the data but also tampers with it.

Types of cryptography attacks

Depending on the type of cryptographic system in place and the information available to the attacker, these attacks can be broadly classified into six types:

1. Brute force attack

   Public and private keys play a significant role in encrypting and decrypting the data in a cryptographic system. In a brute force attack, the cybercriminal tries various private keys to decipher an encrypted message or data. If the key size is 8-bit, the possible keys will be 256 (i.e., 28). The cybercriminal must know the algorithm (usually found as open-source programs) to try all the 256 possible keys in this attack technique.

2. Ciphertext-only attack

   In this attack vector, the attacker gains access to a collection of ciphertext. Although the attacker cannot access the plaintext, they can successfully determine the ciphertext from the collection. Through this attack technique, the attacker can occasionally determine the key.

3. Chosen plaintext attack

   In this attack model, the cybercriminal can choose arbitrary plaintext data to obtain the ciphertext. It simplifies the attacker's task of resolving the encryption key. One well-known example of this type of attack is the differential cryptanalysis performed on block ciphers.

4. Chosen ciphertext attack

   In this attack model, the cybercriminal analyzes a chosen ciphertext corresponding to its plaintext. The attacker tries to obtain a secret key or the details about the system. By analyzing the chosen ciphertext and relating it to the plaintext, the attacker attempts to guess the key. Older versions of RSA encryption were prone to this attack.

5. Known plaintext attack

   In this attack technique, the cybercriminal finds or knows the plaintext of some portions of the ciphertext using information gathering techniques. Linear cryptanalysis in block cipher is one such example.

6. Key and algorithm attack

   Here, the attacker tries to recover the key used to encrypt or decrypt the data by analyzing the cryptographic algorithm.

Preventing cryptography attacks

To prevent cryptography attacks, it is essential to have a strong cryptographic system in place. Some of the ways to achieve this are:

• Regularly update the cryptographic algorithms and protocols to ensure they are not obsolete.

• Ensure that the data is appropriately encrypted so that even if it falls into the wrong hands, it will be unreadable.

• Use strong and unique keys for encryption.

• Store the keys in a secure location.

• Ensure that the cryptographic system is implemented correctly.

• Regularly test the system for vulnerabilities.

• Educate employees about cryptography attacks and how to prevent them.

Final thoughts

The investments in cryptographic solutions are already on the rise; Technavio says the encryption management solutions market will rise by US$ 6.07 billion between 2020 and 2025 at an accelerated CAGR of 17 percent. 

Cryptography attacks are a serious threat to the security of any organization. Organizations can protect their data and communication from being compromised by understanding the various types of attacks and taking steps to prevent them.