How is Hashing a Best Practice in Cyber Security?

The phrase “hashing” is probably familiar to those in the tech and cybersecurity fields, but what exactly does it mean, and why is it used? Fundamentally, hashing changes a string of letters into a different value for security reasons. Despite the frequent confusion between the terms hashing and encryption, hashing is always used for one-way encryption, and hashed data is highly challenging to decode. 

Hashed data cannot be easily decrypted and is intended to be used as a technique of authenticating the validity of an item or piece of data, whereas encryption always provides a decryption key. 

What Is a Hashing Algorithm? 

A hashing algorithm such as MD5 (Message Digest 5) or SHA (Secure Hash Algorithm) produces hashes as its output. For each given piece of information or “message,” these algorithms effectively seek to generate a singular, fixed-length string called the hash value, also known as a “message digest.” Since every file on a computer is simply data expressed in binary code, a hashing algorithm can extract that data and perform a sophisticated calculation, returning the result as a fixed-length string. The hash or message digest of the file is the outcome. 

You can find a cyber security course to help you learn more about hashing algorithms, such as MD5 (Message Digest 5) or SHA (Secure Hash Algorithm).

How Hashing Creates Identity?

Since hashes are non-reversible, one cannot reconstruct a file’s contents just by knowing the hash value of the file from a hashing technique. Though, one may use it to compare two files without understanding what they contain and see if they are identical. 

This makes the notion that each result is uniquely vital to the idea of hashes. We would experience a “collision” and be unable to utilize the hash as an accurate way to identify that particular file if two different files might return the same digest.

Because it is unlikely but not impossible for a collision to occur, more secure algorithms, such as SHA-2, have superseded SHA-1 and MD5. For instance, a quick visual assessment reveals that the contents of the two files plane.jpg and ship.jpg are distinct, and as a result, they should generate different message digests.

The files are not similar, even though we receive a collision when determining the value using MD5. You can see the output from the Terminal. App command prompt on macOS has the same ship.jpg hash value as what we previously obtained using PowerShell.

What Purposes Does Hashing Serve?

As you should have gathered by now, security is the primary purpose of hashing. A hashed value can be used for various purposes, but its primary goal is to encrypt a plaintext value to prevent the disclosure of the contained data. There are numerous uses for hashing in cybersecurity, and these are as follows: 

Message Integrity

An email’s integrity is ensured by the sender applying a one-way hash, sometimes known as a digital signature. Digital signatures guarantee the integrity of the message by using a public/private key combination and a hashing method. 

An email can be digitally signed by first encrypting it with a one-way hashing method and then signing it with the sender’s private key. The same hashing process is used once the message has been received to decrypt it using the sender’s public key. After that, the outcome is checked to see if it matches the original hash value.

File Integrity

For the integrity of files, their hashing functions are similar. Technology providers frequently offer checksums with downloads that are openly accessible. Checksums guarantee that a file or software has not been changed while being transmitted, often an upload from a site to your source host. Checksum results from applying a hashing algorithm to a piece of information; in this situation, a file or program, similar to digital signatures, is applied to documents. Checksums are frequently used in the technology sector to validate files, and security companies use them to monitor the integrity of files. 

Blockchain

Blockchain is a modern technology that makes efficient and unchangeable transactions possible. 

Blockchains function in a peer-to-peer manner, with all devices in the network recording and sharing information about all transactions. However, how can transactions be rendered immutable precisely? It can be done using cryptographic hashing!

The exact manner that hashing functions for the other application cases covered above also applies to blockchains: A hashed value is produced by applying a hash function to a data block. A blockchain is used differently because each transaction necessitates the hashing of an additional data block, which is done using nutcases that are arbitrary or semi-random numbers. Replay attacks occur when an attacker captures network traffic and retransmits it using their system. As one might expect, this can substantially influence a blockchain’s security, and therefore, the usage of nonces assists in thwarting them. 

As learned, hashing is used for various purposes; therefore, seek out cybersecurity certification courses that will help the interested candidates in every way possible. 

Conclusion

To make data untraceable to the human eye, prevent malicious parties from intercepting it, and provide a way to confirm its integrity, hashing has served and continues to be a helpful security tool. Reverse engineering hashed values have gotten more challenging as hashing algorithms have improved in security and sophistication over time. Although it will always be possible to break hashes, doing so without much computational power is becoming increasingly difficult due to the intricate mathematical processes, salts, and nonces requirements. 

You already know that depending on hash identification for AV detection is faulty because two files can have the same functionality and operation without needing the same hash. Despite this, SOUPS are still helpful for security analysts for tasks like exchanging threat-hunting and IOCs. If you work anywhere in computer and network security, you will surely come across them daily. If you want to learn more about hashing, you can join cyber security courses online, which will help you to delve more into hashing.