Cryptographic hashing

While we are talking about hashing, I wanted to explain what it is and why you want to use it. Ensure your company is using SHA-256 or above. SHA-1 has been deprecated due to a SHA-1 collision. A SHA-1 collision occurs when two distinct pieces of data hash to the same message digest. If an attacker can craft a collision, they can use it to create two different files that share the same SHA-1 hash value1.

1 Stevens , Marc, and Elie Bursztein. Announcing the First Sha1 Collision. Google Online Security Blog, Google, 23 Feb. 2017, security.googleblog.com/2017/02/announcing-first-sha1-collision.html.

Although SHA-1 has been deprecated, hmac-sha-1 is still okay to use since it is a secret keyed hash value. What a hashing algorithm provides is integrity. It doesn’t actually encrypt the data, so you can’t read them. Hashing runs a mathematical function on the document that essentially fingerprints it. If anything in the document changes...