A security analyst is reviewing an audit report detailing cryptographic vulnerabilities identified across an enterprise network. Match each observed security incident or technical finding on the left with its underlying cryptographic weakness on the right.
- An attacker retroactively decrypts historical TLS traffic captured from a web server after stealing its long-term private key.Absence of Perfect Forward Secrecy (PFS) in key exchange mechanisms.
- A database review reveals that identical credit card numbers produce identical ciphertext entries across multiple records.Implementation of Electronic Codebook (ECB) mode of operation.
- An attacker recovers plaintext communications from a legacy wireless system by collecting packets transmitted with repeated nonces.Keystream reuse resulting from static initialization vectors (IVs).
- A security audit uncovers an application using a fixed 56-bit symmetric cipher key compiled directly into client software binaries.Inadequate key length susceptible to brute-force key space exhaustion.
Answer
1. Retroactive decryption of captured traffic maps to Absence of Perfect Forward Secrecy (PFS). 2. Identical ciphertext for identical database inputs maps to Electronic Codebook (ECB) mode. 3. Plaintext recovery from repeated nonces maps to Keystream reuse from static IVs. 4. Compiled 56-bit symmetric key maps to Inadequate key length.
Each security finding correctly pairs with its fundamental cryptographic flaw: compromise of past TLS sessions due to lack of PFS; deterministic identical ciphertexts due to ECB block mode; keystream exposure due to static IV reuse; and weak key entropy due to an obsolete 56-bit key length.
Step-by-Step Solution
Key Concept
Cryptographic and Security Control Weaknesses