Description: Password hashing is the process of converting a password into a fixed-size string of characters, typically a hash. This process is fundamental in web application security, as it allows passwords to be stored securely, preventing them from being readable in their original form. Through hashing algorithms like SHA-256 or bcrypt, passwords are transformed into a unique value that represents the original information. One of the most important characteristics of hashing is that it is a one-way process; that is, it cannot be reversed to obtain the original password. This means that even if an attacker gains access to the password database, they will only obtain the hashes and not the plaintext passwords. Additionally, the use of ‘salts’, which are random values added to passwords before hashing, increases security by making the hashes unique, even for identical passwords. In summary, password hashing is an essential technique for protecting sensitive user information in web applications, ensuring that passwords are stored securely and minimizing the risk of exposure in the event of security breaches.
History: The concept of password hashing began to take shape in the 1970s with the introduction of the first authentication systems. One of the earliest hashing algorithms was MD5, developed by Ronald Rivest in 1991. However, as technology advanced and attackers’ capabilities improved, it became evident that MD5 and similar algorithms were not secure enough. This led to the development of more robust algorithms like SHA-1 and, later, SHA-256. In the 2000s, techniques such as the use of ‘salts’ and adaptive hashing algorithms like bcrypt were introduced, which adjust the complexity of hashing based on the available computing power, thereby improving the security of stored passwords.
Uses: Password hashing is primarily used in authentication systems to protect user passwords. By storing only the hash of the password instead of the plaintext password, the risk of an attacker gaining access to user credentials is minimized. It is also used in identity and access management applications, as well as in systems for storing sensitive data where security is paramount. Additionally, it is common in the development of APIs and web services that require user authentication.
Examples: A practical example of password hashing is the use of bcrypt in web applications. Upon registration, the user’s password is converted into a hash using bcrypt, which includes a unique ‘salt’. When the user attempts to log in, the entered password is hashed again and compared to the stored hash. If they match, access is granted. Another example is the use of SHA-256 in password management systems, where passwords are securely stored in databases, thereby protecting user information in the event of an attack.
