Brief Overview: Cryptographic Attacks

Cryptography is a major mechanism used for securing secrets and sensitive data in the IT system. The cryptographic attack is a methodology to bypass implemented cryptographic security employed by exploiting parameters of cryptographic mechanisms and implementation. This blog provides you with a brief idea of existing cryptographic attacks available to compromise IT systems.

(1) Bruteforce attack: This attack simply try to brute force a secret key against the encrypted message to get a plaintext message. Generally secret key is long enough so it is difficult for an attacker to try all possible keys. e.g. If AES uses 256 bits keys, the number of the available keys is 2^256.

(2) Birthday attack: This is another type of Brute force attack that exploits the birthday paradox in probability theory. In this type of attack, It is assumed that the attacker is able to compute a cryptographic hash function for different inputs and the same output is obtained for a different set of inputs.

(3) Dictionary attack: This attack use the brute force technique and used long lists of leaked passwords to identify decryption keys.

(4) Chosen plaintext attack (CPA): This type of attack assumes the attacker has random texts and their corresponding encrypted ciphertexts. The main motive of this attack is to reduce the security of the employed cryptographic security mechanism.

(5) Ciphertext-only attack (COA): This type of attack assumes the attacker has all access to a list of ciphertexts. This attack assumes the attacker has some information related to plaintext also and by analyzing different ciphertexts, it may be decrypted.

(6) Known plaintext attack (KPA): This attack type assumes attackers have access to plaintext message and their corresponding ciphertext. Further, it is used to extract secret keys and codebooks.

(7) Side-channel attack (SCA): This type of attack basically uses leakage of physical parameters such as power consumption, EMI leakage, timing differences, etc. while processing cryptographic operations.

• Timing attack: This attack type exploits how much time different computation takes by the processor in implementing the different cryptographic mechanisms.
• Fault analysis attack: This attack type analyze the behavior of a cryptographic system on encounter with faults.
• Power analysis attack: This attack type utilizes the power consumption while computation of cryptographic implementations to identify secrets by the hardware.
• Electromagnetic attack: This attack type analyzes the electromagnetic radiation emitted while computing to identify cryptographic parameters by the hardware.