From the course: Linux CentOS 7: User and Group Management

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Convert to Shadow Suite

Convert to Shadow Suite - Linux Tutorial

From the course: Linux CentOS 7: User and Group Management

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Convert to Shadow Suite

- [Teacher] In most systems passwords are encoded using a one way hash such as MD5 or sha. A hash function takes a string of characters of any length as input and produces an encoded string of characters of fixed lengths which acts as a kind of signature for the data provided. One way hashes are not reversible and as such you cannot get the plain text from the hash. Note that for these slides I've used an MD5 hash due to its shorter length. Most modern Linux systems use a much longer and more secure sha 512 hash. Even though a one way hash cannot be reversed it can be cracked by taking words from a dictionary, one at a time, hashing them and comparing the output to the hashed password to see if they match. Linux has additional protection against dictionary attacks called a salt. A salt is a set of random characters that are appended to the password before it's hashed. The salt is stored in the password files with the hash. A hacker who doesn't have access to the salt wouldn't be able…

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