Page 209 - Cyber Defense eMagazine Annual RSA Edition for 2024

The Quick “Cliff-notes” Version

Hashing, for the non-mathematical cyber professional, is like creating a unique fingerprint for your data.
Imagine you have a document with super important information. You can’t just lock it away, because
sometimes you need to check if the information inside is still the same.

Here’s how hashing works:

• Hash Function: This is like a special recipe that takes any kind of data (your document) and
cooks it up into a fixed-size code (the fingerprint). No matter how long your document is, the hash
function always gives you a short, unique code.
• The Hash: This is the code generated by the hash function, like the actual fingerprint. It’s much
shorter than the original data, but it’s still unique to that specific data.

Here’s why hashing is cool for cybersecurity:

• Verifying Data Integrity: Let’s say you download a file from the internet. You can run the file
through a hash function and compare the generated hash with the one provided by the source. If
the codes match, you know the file hasn’t been tampered with during download.
• Secure Password Storage: Websites don’t actually store your password. Instead, they store a
hash of your password. When you log in, they hash your entered password and compare it to the
stored hash. If they match, you’re in! This way, even if a hacker steals the stored data, they can’t
easily crack your password from the hash.

Things to Remember:

• Hashing is a one-way street. You can’t get the original data back from the hash, just like you can’t
recreate the document from the fingerprint.
• Different data will have different hashes, even if they seem similar. This makes it hard to fake data
by just copying someone else’s hash.
• There are different hash functions, some more secure than others. Cryptographically secure hash
functions are used for important tasks like password storage.

I hope this explanation helps! Hashing is a fundamental concept in cybersecurity, and understanding it
will give you a leg up in protecting information.

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