Hashing & Security

To understand hashing and its related attack types, let’s follow the story of SecureTech, a growing software company, and their journey to protect their digital assets.

The Hashing Fortress

SecureTech uses hashing to secure user passwords and verify data integrity. Hashing is a process that converts input data of any size into a fixed-length string of characters, called a hash value or digest.Here’s how it works:

1. When a user creates a password, SecureTech’s system runs it through a hash function.
2. The hash function processes the password in blocks, combining each block’s result with the next block’s input.
3. The final output is a unique, fixed-length hash value.
4. SecureTech stores this hash value, not the original password.

For example, using SHA-256:

• Input: “password123”
• Output: “ef92b778bafe771e89245b89ecbc08a44a4e166c06659911881f383d4473e94f”

This process is deterministic (same input always produces the same output) and designed to be one-way (theoretically impossible to reverse).

The Attackers Emerge

As SecureTech grows, it attracts the attention of cybercriminals. They employ various attack types targeting the hashing system:

1. Brute Force Attack

Attacker Alex tries every possible combination to guess a password, hoping to find a match for a stolen hash.Prevention:

• SecureTech implements rate limiting on login attempts.
• They enforce strong password policies, increasing the time needed for brute force attacks.

2. Dictionary Attack

Hacker Beth uses a list of common passwords, hashing each to compare against stolen hash values.Prevention:

• SecureTech bans common passwords.
• They implement multi-factor authentication (MFA) to add an extra layer of security.

3. Rainbow Table Attack

Cybercriminal Charlie uses precomputed tables of hash values for common passwords to quickly look up matches.Prevention:

• SecureTech adds “salt” (random data) to each password before hashing, making rainbow tables ineffective.

4. Collision Attack

Researcher Dana attempts to find two different inputs that produce the same hash value, potentially allowing for forgery.Prevention:

• SecureTech uses modern, collision-resistant hash functions like SHA-256 or SHA-3.
• They regularly update their hashing algorithms to stay ahead of new vulnerabilities.

5. Length Extension Attack

Hacker Evan tries to append data to a message without knowing the secret key, exploiting vulnerabilities in some hash functions.Prevention:

• SecureTech uses hash functions resistant to length extension, like SHA-3 or BLAKE2.
• They implement HMAC (Hash-based Message Authentication Code) for added security.

SecureTech’s Defense Strategy

To combat these threats, SecureTech implements a multi-layered approach:

1. They use Argon2, a modern key derivation function, for password hashing.
2. All passwords are salted before hashing to prevent rainbow table attacks.
3. They implement MFA across all user accounts.
4. Regular security audits are conducted to identify and patch vulnerabilities.
5. Employee training programs raise awareness about password security.

By understanding the intricacies of hashing and potential attack vectors, SecureTech successfully protects its users’ data, maintaining trust and integrity in their growing digital ecosystem.