Press "Enter" to skip to content

Ian Marrero Posts

Detecting Unauthorized Intrusions Using Windows Security Event Logs

Published August 6, 2023

Maintaining the security of a Windows system is essential to protect sensitive data and prevent unauthorized access. One powerful tool in detecting potential security breaches is the Windows Security Event Logs. These logs provide valuable information about system activities, user actions, and potential intrusion attempts. In this article, we will explore how to leverage Windows Security Event Logs, focusing on specific Event IDs to monitor for unauthorized intrusions effectively. Windows Security Event Logs are invaluable in detecting unauthorized intrusions and…

(More…)Detecting Unauthorized Intrusions Using Windows Security Event Logs

cybersecurityevent logswindows

A Comprehensive Guide to Securing SSH on Ubuntu 22.04

Published July 23, 2023

SSH (Secure Shell) is a widely used protocol for securely accessing remote servers. However, its popularity also makes it a target for potential attackers. To ensure the safety of your Ubuntu 22.04 server, it is crucial to implement robust security measures for SSH. In this article, we will discuss essential steps to secure SSH on Ubuntu 22.04, safeguarding your server from unauthorized access and potential security breaches. Locate the line containing PermitRootLogin and set it to no: Save the file…

(More…)A Comprehensive Guide to Securing SSH on Ubuntu 22.04

cybersecuritylinuxssh

[Errno 28] No space left on device – Updating VMWare ESXI 6.7

Published February 3, 2022

When updating VMWare ESXI 6.7, which runs my homelab, I always get the error “[Errno 28] No space left on device”. But wait… There is enough space on the disk! A quick search on the package name returned several articles addressing the same issue. It is a common issue with VMWare ESXI 6.7. To fix the issue, the package needs to be installed manually. Let’s begin by enabling HTTP Client in ESXI. The first step is pulling the latest version…

(More…)[Errno 28] No space left on device – Updating VMWare ESXI 6.7

esxihomelabvmware

Verify if a media device or file is bootable

Published August 26, 2021

To verify if a removable media (e.g. USB, DVD, or ISO) is bootable, you could use file tool on Linux systems. The command file -s /path/to/media reads block special files, such as partitions, and outputs the information. To test this, I inserted RHEL 8.2 Installation ISO as a disk in a VM. The device path is /dev/sr0. Once I verified the disk is accessible, I ran file -s /dev/sr0. The output for RHEL Installation ISO shows the disk as a…

(More…)Verify if a media device or file is bootable

linux

I am CISSP Certified!

Published April 8, 2021

I passed the CISSP exam in April 2021! Such a difficult exam! The exam is nothing like the practice tests you can find available for free or for purchase. Throughout the exam, I felt unprepared; halfway through the exam I felt like I was failing, that I should take mind-notes for my next attempt. To my surprised, I passed at 100 questions at around 110 minutes into the exam. This is how I did it…

(More…)I am CISSP Certified!

certificationsCISSPcybersecuritypersonal