Networking

Firejail is a powerful and flexible Linux security tool designed to sandbox applications and reduce the risk of security vulnerabilities, isolation breaches, and system-wide compromises. It works by leveraging Linux namespaces, seccomp-bpf, and other security mechanisms to isolate applications within a confined environment, thereby minimizing the impact of potential exploits. The tool is lightweight, easy to use, and does not require significant changes to the system or applications.

Failtoban is a security tool designed primarily to prevent unauthorized access to servers by detecting and blocking IP addresses that make repeated unsuccessful login attempts. These login failures often indicate brute-force attacks, where attackers try various password combinations to gain unauthorized access to an account. Failtoban enhances server security by analyzing log files for patterns of failed login attempts and then blacklisting the IP addresses responsible.

Network scanning is a fundamental task for system administrators, network engineers, and security professionals. By scanning a network, one can discover devices connected to it, identify vulnerabilities, and monitor the overall health of the network. Two widely used tools for network discovery and reconnaissance are arp-scan and Netdiscover. Both tools utilize ARP (Address Resolution Protocol) to map out the devices within a network, but they have different features and approaches. This article will explore both tools, their functionalities, and how to use them for network scanning.

Pi-hole is a free, open-source software that acts as a DNS sinkhole. It effectively prevents devices on your network from reaching known ad servers by rerouting requests to an internal server instead of the actual destination. Originally designed to run on a Raspberry Pi single-board computer, Pi-hole can now be installed on a variety of platforms, including virtual machines, Docker, and even cloud servers

The SSH config file (~/.ssh/config) allows users to define preferences and settings for different SSH connections, streamlining remote access and improving overall security and convenience. By specifying various configuration options for individual hosts, users can avoid repeatedly entering lengthy commands or parameters every time they connect to remote systems.

SSH local tunneling involves forwarding a local port to a remote server or service through an encrypted SSH connection. Essentially, it creates a secure "tunnel" from your local machine to a remote destination, and any traffic sent to a specified local port is forwarded to a remote server or servic

Stunnel is an open-source proxy designed to add SSL/TLS encryption to existing client-server applications without requiring any modifications to the applications themselves. It creates a secure tunnel for communications, allowing data to be encrypted as it travels over potentially insecure networks, such as the internet.

A jump server is a special-purpose server that acts as an intermediary between users and other servers in a private network. By routing all SSH connections through the jump server, organizations can enforce stricter access controls, monitor traffic, and reduce the attack surface of their internal servers.

SOCKS, which stands for "Socket Secure," is an internet protocol that facilitates the transfer of data between a client and a server through a proxy server. Unlike HTTP proxies, which are limited to web traffic, SOCKS proxies can handle any kind of traffic generated by any protocol, making them a versatile option for a range of applications.