When you troubleshoot or audit a system by handling its log files, it might be useful to get the first lines of them in order to know, the timestamp or date of when the file was created or newly rotated,…
One of the most commonly used commands in Linux systems to handle the date inside the files is the tail command which basically, prints the last lines of it as you may presume with the command name. Although it seems…
Running processes in the background in Linux systems represents one of the most common ways to perform some batch process or long running process in parallel, without keeping busy your current terminal and consequently forcing you to wait until the…
Trivy is a vulnerability scanning tool mainly used for containers images, that helps cybersecurity professionals to obtain such information from them by either running it on demand, or automating its execution in any CI pipeline security testing step. It is…
Do you need in your cybersecurity program a tool for assessing the security and hardening status of your organisation Linux systems without cumbersome deployments or setups? If so, then the tool you are looking for is Lynis which is a…
Nikto is an open source web application scanning tool which helps cybersecurity professionals to cover such activities in an easy, fast paced and in a command line manner. Thanks to its simplicity, it is really a piece of cake to…
The asymmetric encryption is one of the security advances that makes the internet connections and online transactions trustable. Without this trust, nobody are willing to do business or perform any purchase on any e-commerce no matter how fast and convenient…
One of my favourite Linux commands is less which is also the one that I use the most when the troubleshooting activities needs to review some sort of logs, config files, audit files and so on. Thanks to this great…
Imagine a one way function that is able to map an input with infinite possibilities to a fixed length and “unique” output. Note that unique is quoted since theoretically is not possible to map an infinite set to a finite…
The HMAC stands for “Hash-based Message Authentication Code” and it could be based on the previous hash functions explained before to calculate it. It serves for integrity and authentication of a message when using symmetric encryption or any shared secret…
The symmetric encryption is the most used cryptographic operation to protect the confidentiality of the information whether it is personal information or corporate sensitive data. The main reason why symmetric encryption is preferred in most of the cases instead of…
This post will show how to convert certificates or keys between the 2 possible formats available for this kind of files with openssl: PEM or DER. But, before jumping in, let’s explain what PEM or DER stands for. What is…
