Question

Consider a password hash function that works as follows on a system where the password must contain only letters: Step 1. Take each letter in the password and replace it with a number representing its place in the alphabet. Step 2. Take each number from Step 1, multiply it by 2 , and add 1 . Step 3. Combine the resulting numbers, separated by Os, into a single string. This string is the encrypted password. a. Given the user password "user", what would this hashing algorithm produce as the final encrypted password? b. Comment on this hashing algorithm in terms of the security it provides for user passwords.

Short answer

The encrypted password is '430391137'. The algorithm is simple and predictable, offering weak security.

Step-by-step solution

Convert Letters to Numbers

First, find the numerical place of each letter in the English alphabet: 'u'=21, 's'=19, 'e'=5, 'r'=18.

Apply Transformation

For each number obtained in Step 1, multiply by 2, and add 1 to get a new number. For 'u' (21): \(21 \times 2 + 1 = 43\). For 's' (19): \(19 \times 2 + 1 = 39\). For 'e' (5): \(5 \times 2 + 1 = 11\). For 'r' (18): \(18 \times 2 + 1 = 37\).

Combine Transformed Numbers

Join the numbers from Step 2 into a string, separated by 0: '43', '39', '11', '37' becomes '43_39_11_37'. After removing the underscore, we get '430391137'.

Key concepts

Password Security

Password security is crucial in keeping your online accounts safe from unauthorized access. A strong password acts like a shield against cyber threats and identity theft. Choosing the right method to store passwords adds an extra layer of protection. Instead of storing plain text passwords, which hackers can easily exploit, it is safer to store encrypted versions. Encryption disguises your password and makes it unreadable to anyone without the right decryption key.

The process helps keep your sensitive information, like online banking credentials, emails, or social media accounts, secure. Simple password operations like converting letters to numbers followed by basic operations, as seen in the exercise, are less secure. They can be easily reversed and might not provide the necessary level of protection against modern threats.

• Never use simple hashing algorithms without salt or additional security measures.
• Consider using algorithms that have been tested for strength and reliability.
• Always prioritize keeping passwords as concealed as possible when stored.

Hash Function

A hash function is a mathematical process that transforms an input, like a password, into a fixed-size string of characters. This transformed input is often called a "hash code." Hash functions are integral to password security because they conceal the original data while allowing the password to be verified during user login operations. In essence, the same input will always produce the same hash; a crucial property for password checks.

However, the simplicity of the function used in the exercise presents a security risk. It creates distinct patterns that make it easier for attackers to decipher the original password. In contrast, modern hash functions, like SHA-256, utilize complex transformations that make reverse-engineering practically impossible.

• A good hash function distributes input data uniformly across the output space.
• It's computationally hard to reverse a hash function.
• Different hashes should look completely different, even if the passwords are very similar.

Alphabetic to Numeric Conversion

Alphabetic to numeric conversion transforms each letter in a password into a numeric value based on its position in the alphabet. For example, 'A' is converted to 1, 'B' to 2, and so on. This method of conversion is straightforward and acts as the first layer of conversion in the hashing process described in the exercise.

While this method is simple and easy to implement, it is quite predictable and can pose security challenges. Since the number representations are straightforward and serial (A=1, B=2), it does not sufficiently obfuscate the original text. Anyone with an understanding of this conversion can easily reverse it.

• This conversion alone is not enough for secure password storage.
• It's important to combine with other encryption methods to enhance security.
• Basic transformations should be part of a more complex and secure process.

Encryption Method

An encryption method is a process used to encode information, such as passwords, so that it cannot be easily understood by unauthorized users. The exercise showcases a basic encryption method involving numeric conversions and simple arithmetic operations. This method, though methodical, falls short in terms of complexity and security.

Effective encryption methods should not only transform the password but also make the transformation irreversible without a specific key or method. Advanced encryption techniques, like AES (Advanced Encryption Standard), employ permutations, and substitutions to make it exponentially difficult for hackers to retrieve the original message without the decryption key.

• Complex encryption methods resist plain-text attacks.
• More sophisticated methods are recommended for sensitive data.
• Encryption should be regularly updated to address new security vulnerabilities.