February 24, 2022
6 min read

How to Prevent a Replay Attack in 2022

A replay attack is when the hacker or cybercriminal can sneakily intercept your data package and then repeat it back imitating you.

Povilas M.
Security Expert
It’s 2022, and you are able to order fast food on the Internet. So, you order one hamburger for delivery. Now, what if someone intercepts your package? They can easily steal the burger! Tragic, right? The same can happen in a digital environment, and it’s called a replay attack. Our article will explain how to prevent this kind of attack, so let’s get started!

Replay attacks – what are they?

A replay attack is when the attacker, often called a sniffer (because it’s referred to as sniff communication), can sneakily intercept your package (data transmitted to the server) and then play it back imitating you. It’s like taking a videotape of a party, copying it, and using the copy to pretend you are at your party.
The only difference is that the speed at which this happens is much faster. The hacker can have your data in just a few instances. In addition, instead of using physical media, the human element is replaced with a computer program.
The term “replay” can be confusing because it describes more than just this phenomenon. Replay attacks are often used in the context of cryptography. These are types of attacks that try to decrypt secret messages by replaying them.

How to prevent a replay attack in 2022?

Advanced digital cryptography

There are many ways you can prevent being fooled by a replay attack, but we will explain the general idea behind them. End-to-end encryption and symmetric, random keys seem to be the most efficient solution.
It’s simple: during the initial handshake (communication and successful connection), the server sends a secret key to the user which is used for future communication. A network sniffer would not know this key because it does not have access to the data that is transmitted after that handshake.
This key (a piece of information) is called “symmetric” because you share it with the server, and there is only one instance of this key. While in a replay attack, the attacker would use this key, too. So if you were to compare keys (for example byte by byte), they would not match and your software would reject the replay attack. This is the general idea behind replay attack prevention. Advanced digital cryptography is one of the most versatile solutions for almost all cyber attack prevention.
Hence, apps that offer end-to-end encrypted communication are great ways to prevent sniffers and other forms of data breaches. Kraden is one of those apps. Thanks to AES-256 end-to-end encrypted communications, and P2P connectivity, everyone who uses Kraden can be sure that their messages and files are only seen by them and the intended receiver(s).

One-time use passwords

Another security feature is one-time use passwords for each transaction or login. When this option is enabled, your password changes according to a certain algorithm every time you log in. The server does not store the same password again, so replay attacks are completely prevented.
But what if someone manages to record your original password? It might be used for replay attacks later…

Third-party authentication

An option that’s last on our list but definitely not the least notable. Nowadays, it’s becoming more and more common to connect your phone number or another device with your accounts. This connection can be used as a second layer of protection. If someone were to try logging in with their password, the server would request an SMS verification. Basically, third party authentication can be requested from someone within your organization or just be enabled in a form of 2FA.


IRP or incident response plans are designed to prepare your company for the event of a data breach. The goal is to quickly identify an incident, collect evidence, understand what happened to the largest possible extent, and determine who was responsible for it.
IRP plans are rough guides used during cyber attacks and are aimed to help people get the basic knowledge of what to do in case of facing an attack. IT support might not be available right away, so at least some pointers are nice. It’s not always easy to identify the most efficient way to deal with an attack. Luckily there is no need to reinvent the wheel for this one; you can find replay attack prevention strategies in existing IRP plans or buy one from a consultant that sells and devises them.

Replay attacks – what does the future hold?

Even though digital cryptography has seen a lot of improvements, hackers are not standing still. Since replay attack prevention focuses on the human element, there is no absolute algorithm for preventing them. People can still not be aware of clever social engineering or other tactics that hackers may employ to compromise their connections.
The biggest hope is that more people will be sufficiently knowledgeable on cyber security and won’t even think about such problems. However, it doesn’t hurt to know how to prevent replay attacks because you may encounter one without ever knowing about it!
For companies, employing designated IT support and cybersecurity experts are an integral part of enforcing prevention against such attacks.

How to recover from a replay attack?

It’s not as difficult to prevent replay attacks as it is complicated to recover from them.
Basically, replay attacks can be prevented by implementing digital cryptography or preventing people from logging into online accounts multiple times using the same password, etc.. The problem is that once an account has been breached, replay attacks become increasingly likely and can be hard to detect.
The most important action is to make sure that there is a plan for recovering data and accounts in the unfortunate event of an attack. For example, an incident response plan should include steps taken at the very beginning of the breach while gathering evidence, which passwords have been used previously. This can be a great foundation for recovery.


Replay attacks are among the most complicated cyber security issues in today’s world. It’s not always easy to identify systems that use replay attacks or whether or not replay attack prevention is enabled. However, it’s good to know how to prevent them in case of an encounter. Implementing a plan, eliminating the reuse of passwords and encrypting communications seem like a perfect starting point.
More blog posts
April 10, 2023
8 min read
Proxy vs VPN: What Are the Differences?
VPNs have more features than a proxy, but they are more expensive. However, there are more pros and cons when choosing between a VPN or a Proxy.
Povilas M.
Security Expert
March 16, 2023
5 min read
What Is a Remote Wipe? Remotely Delete Your Phone
A remote wipe is a remote deletion of data from a device without having the device physically. Remote wipes can run on mobile phones, desktops, etc.
Ross K.
Security Expert
A security and IT company on a mission to make everyone’s privacy a default.
© 2022 Dragon Secure GmbH. Bahnhofstrasse 32, 6300, Zug, Switzerland