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Email to Profile: Social Media Search and Free Lookup Tools

Introduction Connecting an email address to a real person can reveal valuable insights. With email-to-profile...

OSINT

Advanced Free Email Lookup and Reverse Search Techniques

Introduction Email addresses are often the keys to digital identities. With the right tools, you...

How to Use Pentest Copilot in Kali Linux

Introduction Artificial Intelligence is changing how cybersecurity professionals work, especially in penetration testing. Tools that...

Install Zabbix on Ubuntu 18.04: Server Setup with MySQL Backend

By Cyber Defence on July 28, 2026

Zabbix is a mature open-source infrastructure monitoring platform that collects metrics from network devices, servers, virtual machines, and applications. It supports both agent-based monitoring and agent-less monitoring via SNMP, IPMI, and JMX. The Zabbix agent is lightweight and runs on Linux,...

Install Gradle on Ubuntu 18.04: Set Up OpenJDK and Environment

By Cyber Defence on July 28, 2026

Gradle is a powerful open-source build automation tool used primarily for Java, Kotlin, Groovy, and Android projects. It combines the flexibility of Apache Ant with the dependency management of Apache Maven, but replaces XML configuration files with Groovy or Kotlin DSL...

Install TeamViewer on Ubuntu 18.04: Download the .deb and Set Up

By Cyber Defence on July 28, 2026

TeamViewer is a proprietary cross-platform remote access application for remote control, desktop sharing, file transfer, and online meetings. It is one of the most widely used remote support tools in the world, available for Windows, macOS, Linux, iOS, and Android. TeamViewer is not included in the Ubuntu repositories because it is proprietary software. This guide covers how to install TeamViewer on Ubuntu 18.04 using the official .deb package. The same steps apply to Ubuntu 16.04, Debian, Linux Mint, and Elementary OS. Install TeamViewer on Ubuntu: Download the .deb Package Download the official TeamViewer .deb package. The _amd64.deb suffix indicates this package is for 64-bit x86-64 systems. For ARM-based machines, download the appropriate package from the TeamViewer Linux downloads page: Install the package using apt. The ./ prefix tells apt this is a local file path, not a package name from the repositories: At the ‘Do you want to continue?’ prompt, type Y and press Enter. The installer resolves and installs the Qt5 library dependencies that TeamViewer requires for its graphical interface. TeamViewer also registers its official APT repository automatically during this process, which enables future updates. Launch TeamViewer, Accept the License, and Start a Session Start TeamViewer from the Activities menu by searching for “TeamViewer,” or from the terminal: The first time TeamViewer opens, click Accept License Agreement before the main interface loads. The main window shows two important values: To connect to a remote machine, enter its TeamViewer ID in the Partner ID field and click Connect. You will be prompted for the remote machine’s current session password. A few capabilities worth knowing about: How TeamViewer Updates Work and What to Know About the...

Install Nagios Core on Ubuntu 18.04: Build from Source Guide

By Cyber Defence on July 28, 2026

Nagios is one of the most widely used open-source infrastructure monitoring systems in the world. It tracks servers, networks, applications, services, and processes, and sends alerts by email or other channels when something fails or performs below threshold. Ubuntu 18.04 includes...

Email to Profile: Social Media Search and Free Lookup Tools

By 0xSnow on November 3, 2025

Introduction Connecting an email address to a real person can reveal valuable insights. With email-to-profile searches, social media lookups, and reverse search tools, you can uncover linked accounts, public posts, and verified identities. This process is common in cybersecurity, recruiting,...

Advanced Free Email Lookup and Reverse Search Techniques

By 0xSnow on November 3, 2025

Introduction Email addresses are often the keys to digital identities. With the right tools, you can uncover social media profiles, online activity, and even business records associated with an email. This process, known as email lookup or reverse email search,...

How to Use Pentest Copilot in Kali Linux

By 0xSnow on November 1, 2025

Introduction Artificial Intelligence is changing how cybersecurity professionals work, especially in penetration testing. Tools that once required manual effort are now becoming smarter and more efficient. One of the most interesting AI-assisted tools available today is Pentest Copilot, developed by...

How to Use the Windows Registry to optimize and control your PC.

By Tamilselvan S on October 30, 2025

The Windows Registry Editor lets you easily view and control critical Windows system and application settings. It acts as a central hub, storing configuration information for your hardware, software, and personal preferences. Type regedit in the Start menu or the...

MQTT Security: Securing IoT Communications

By 0xSnow on October 30, 2025

In the rapidly expanding Internet of Things (IoT) ecosystem, billions of devices are constantly exchanging data from smart home appliances and industrial sensors to connected vehicles and healthcare monitors. Behind this seamless communication lies a lightweight protocol that powers most...

Set Up a UFW Firewall on Ubuntu 18.04: Allow, Deny, and Manage

By Cyber Defence on July 23, 2026

A properly configured firewall is one of the most important layers of security for any internet-facing server. UFW (Uncomplicated Firewall) is a user-friendly front-end for managing iptables rules that ships pre-installed on Ubuntu. Its defaults are sensible: block all incoming connections, allow all outgoing connections. No outside traffic reaches your server unless you explicitly open a port. This guide covers how to configure a UFW firewall on Ubuntu 18.04, from setting default policies and application profiles to writing allow and deny rules for specific ports, IPs, and subnets. Configure UFW Firewall on Ubuntu: Defaults, SSH, and Application Profiles If UFW is not installed, add it with: Check the current status: Application profiles. When you install a service with apt, it registers a profile in /etc/ufw/applications.d/. List all available profiles: Use a profile name or a port number interchangeably when writing rules. To see what ports a profile covers: Allow SSH before enabling UFW. This is the most critical step. If you enable UFW without an SSH rule and you are on a remote server, you lose access immediately: If your SSH daemon runs on a non-standard port, use the port number instead, for example sudo ufw allow 4422/tcp. Enable UFW: Type y at the prompt to confirm. Allow Port Ranges, Specific IPs, Subnets, and Network Interface Rules Common...

Install Skype on Ubuntu 18.04: .deb Package and Auto-Updates

By Cyber Defence on July 24, 2026

Skype is one of the most widely used communication platforms in the world. It lets you make free audio and video calls over the internet, send instant messages, share files, and make affordable calls to mobile and landline numbers worldwide. Microsoft...

Install PHP on Ubuntu 18.04: Apache, Nginx FPM, and Ondrej PPA

By Cyber Defence on July 24, 2026

PHP is the most widely used server-side scripting language for web development. Ubuntu 18.04 ships with PHP 7.2 in its default repositories, which is fully compatible with WordPress, Laravel, Drupal, and Nextcloud. The installation method differs based on which web server you are...

Install NetBeans IDE on Ubuntu 18.04 with Snap and OpenJDK 8

By Cyber Defence on July 21, 2026

NetBeans is a free, open-source, cross-platform IDE developed by the Apache Software Foundation. It was one of the first IDEs to ship with a drag-and-drop GUI builder for Java Swing applications, and it has since grown into a full-featured development environment...