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02/15/2025   LinuxSecurity.com
Update to 133.0.6943.98 CVE-2025-0995: Use after free in V8 CVE-2025-0996: Inappropriate implementation in Browser UI CVE-2025-0997: Use after free in Navigation CVE-2025-0998: Out of bounds memory access in V8
02/15/2025   LinuxSecurity.com
Update to upstream 2.1-48. 20250211 Addition of 06-bf-06/0x07 microcode (in intel-ucode/06-97-02) at revision 0x38; Addition of 06-bf-07/0x07 microcode (in intel-ucode/06-97-02) at revision 0x38; Addition of 06-bf-06/0x07 microcode (in intel-ucode/06-97-05) at revision 0x38; Addition of 06-bf-07/0x07 microcode (in intel-ucode/06-97-05) at revision 0x38;
02/15/2025   LinuxSecurity.com
Update to 133.0.6943.98 CVE-2025-0995: Use after free in V8 CVE-2025-0996: Inappropriate implementation in Browser UI CVE-2025-0997: Use after free in Navigation CVE-2025-0998: Out of bounds memory access in V8
02/15/2025   LinuxSecurity.com
Multiple vulnerabilities were fixed in trafficserver, a caching proxy server. CVE-2024-38479
02/15/2025   LinuxSecurity.com
C'©dric Krier has found that trytond, the Tryton application server, accepts compressed content from unauthenticated requests which makes it vulnerable to zip bomb attacks (see DLA 4022-1).
02/15/2025   LinuxSecurity.com
Multiple vulnerabilties have been found in freelrdp2, a free implementation of the Remote Desktop Protocol (RDP). The vulnerabilties potentially allows authentication bypasses on configuration errors, buffer overreads, DoS vectors, buffer overflows or accessing files
02/14/2025   Linux Today

AirDrop is a proprietary wireless ad hoc service. The service transfers files among supported Macintosh computers and iOS devices by means of close-range wireless communication. AirDrop is not available for Linux. We recommend the best free and open source alternatives.

The post Best Free and Open Source Alternatives to Apple AirDrop appeared first on Linux Today.

02/14/2025   Linux Today

Beelzebub is an open-source honeypot framework engineered to create a secure environment for detecting and analyzing cyber threats. It features a low-code design for seamless deployment and leverages AI to emulate the behavior of a high-interaction honeypot.

The post Beelzebub: Open-source honeypot framework appeared first on Linux Today.

02/14/2025   Linux Today

This article will show you how to install Tiny Tiny RSS on Linux using Docker and then how to add a new RSS feed, add plugins, themes, and more.

The post How to Install Tiny Tiny RSS Using Docker on PC (Ultimate Guide) appeared first on Linux Today.

02/14/2025   Linux Today

Learn how to install Speedtest Tracker with Docker and monitor your internet speed with real-time results.

The post How to Install Speedtest Tracker to Monitor Your Internet Speed appeared first on Linux Today.

02/13/2025   Linux Today

In the world of Linux, terminal multiplexers are essential tools for developers, system administrators, and power users, as they allow you to manage multiple terminal sessions within a single window, making your workflow more efficient and organized.

The post Zellij: A Modern Terminal Multiplexer for Linux appeared first on Linux Today.

02/13/2025   Linux Today

Chezmoi is an incredible CLI tool that makes it easier to manage your system and software configuration dotfiles across multiple systems.

The post Chezmoi: Manage Your Dotfiles Across Multiple Linux Systems appeared first on Linux Today.

02/13/2025   Linux Today

Discover a step-by-step guide to change the default version of Java using the CLI and GUI methods on the Ubuntu system.

The post How to Change Java Version on Ubuntu (CLI and GUI) appeared first on Linux Today.

02/13/2025   Linux Today

Arch may soon become an officially offered distro on Microsoft's Windows Subsystem for Linux, expanding its reach to Windows users.

The post Microsoft’s WSL May Soon Embrace Arch Linux appeared first on Linux Today.

02/13/2025   Linux Today

To provide an insight into the quality of software that is available, we have compiled a list of 15 console email clients. Hopefully, there will be something of interest for anyone who wants to efficiently manage their mailbox from the terminal.

The post 15 Best Free and Open Source Console Email Clients appeared first on Linux Today.

02/13/2025   Linux Today

Starting from WSL version 2.4.8, we can install Ubuntu on WSL from a tar file, without using the Microsoft Store on Windows.

The post You Can Now Install Ubuntu on WSL Using the New Tar-Based Format appeared first on Linux Today.

02/13/2025   Linux Journal
Streamline Your Logs: Exploring Rsyslog for Effective System Log Management on Ubuntu

Introduction

In the world of system administration, effective log management is crucial for troubleshooting, security monitoring, and ensuring system stability. Logs provide valuable insights into system activities, errors, and security incidents. Ubuntu, like most Linux distributions, relies on a logging mechanism to track system and application events.

One of the most powerful logging systems available on Ubuntu is Rsyslog. It extends the traditional syslog functionality with advanced features such as filtering, forwarding logs over networks, and log rotation. This article provides guide on managing system logs with Rsyslog on Ubuntu, covering installation, configuration, remote logging, troubleshooting, and advanced features.

Understanding Rsyslog

What is Rsyslog?

Rsyslog (Rocket-fast System for Log Processing) is an enhanced syslog daemon that allows for high-performance log processing, filtering, and forwarding. It is designed to handle massive volumes of logs efficiently and provides robust features such as:

  • Multi-threaded log processing

  • Log filtering based on various criteria

  • Support for different log formats (e.g., JSON, CSV)

  • Secure log transmission via TCP, UDP, and TLS

  • Log forwarding to remote servers

  • Writing logs to databases

Rsyslog is the default logging system in Ubuntu 20.04 LTS and later and is commonly used in enterprise environments.

Installing and Configuring Rsyslog

Checking if Rsyslog is Installed

Before installing Rsyslog, check if it is already installed and running with the following command:

systemctl status rsyslog

If the output shows active (running), then Rsyslog is installed. If not, you can install it using:

sudo apt update
sudo apt install rsyslog -y

Once installed, enable and start the Rsyslog service:

sudo systemctl enable rsyslog
sudo systemctl start rsyslog

To verify Rsyslog’s status, run:

systemctl status rsyslog

Understanding Rsyslog Configuration

Rsyslog Configuration Files

Rsyslog’s primary configuration files are:

  • /etc/rsyslog.conf – The main configuration file

  • /etc/rsyslog.d/ – Directory for additional configuration files

Basic Configuration Syntax

Rsyslog uses a facility, severity, action model:

02/11/2025   Linux Journal
Linux Networking Protocols: Understanding TCP/IP, UDP, and ICMP

Introduction

In the world of Linux networking, protocols play a crucial role in enabling seamless communication between devices. Whether you're browsing the internet, streaming videos, or troubleshooting network issues, underlying networking protocols such as TCP/IP, UDP, and ICMP are responsible for the smooth transmission of data packets. Understanding these protocols is essential for system administrators, network engineers, and even software developers working with networked applications.

This article provides an exploration of the key Linux networking protocols: TCP (Transmission Control Protocol), UDP (User Datagram Protocol), and ICMP (Internet Control Message Protocol). We will examine their working principles, advantages, differences, and practical use cases in Linux environments.

The TCP/IP Model: The Foundation of Modern Networking

What is the TCP/IP Model?

The TCP/IP model (Transmission Control Protocol/Internet Protocol) serves as the backbone of modern networking, defining how data is transmitted across interconnected networks. It consists of four layers:

  • Application Layer: Handles high-level protocols like HTTP, FTP, SSH, and DNS.

  • Transport Layer: Ensures reliable or fast data delivery via TCP or UDP.

  • Internet Layer: Manages addressing and routing with IP and ICMP.

  • Network Access Layer: Deals with physical transmission methods such as Ethernet and Wi-Fi.

The TCP/IP model is simpler than the traditional OSI model but still retains the fundamental networking concepts necessary for communication.

Transmission Control Protocol (TCP): Ensuring Reliable Data Transfer

What is TCP?

TCP is a connection-oriented protocol that ensures data is delivered accurately and in order. It is widely used in scenarios where reliability is crucial, such as web browsing, email, and file transfers.

Key Features of TCP:
  • Reliable Transmission: Uses acknowledgments (ACKs) and retransmissions to ensure data integrity.

  • Connection-Oriented: Establishes a dedicated connection before data transmission.

  • Ordered Delivery: Maintains the correct sequence of data packets.

  • Error Checking: Uses checksums to detect transmission errors.

How TCP Works:
  1. Connection Establishment – The Three-Way Handshake:

02/06/2025   Linux Journal
Leveraging Tmux and Screen for Advanced Session Management

Introduction

In the realm of Linux, efficiency and productivity are not just goals but necessities. One of the most powerful tools in a power user's arsenal are terminal multiplexers, specifically tmux and Screen. These tools enhance the command line interface experience by allowing users to run multiple terminal sessions within a single window, detach them and continue working in the background, and reattach them at will. This guide delves into the world of tmux and Screen, showing you how to harness their capabilities to streamline your workflow and boost your productivity.

Understanding Terminal Multiplexers

What is a Terminal Multiplexer?

A terminal multiplexer is a software application that allows multiple terminal sessions to be accessed and controlled from a single screen. Users can switch between these sessions seamlessly, without the need to open multiple terminal windows. This capability is particularly useful in remote session management, where sessions need to remain active even when the user is disconnected.

Key Features and Benefits
  • Session Management: Keep processes running even after disconnecting.
  • Window Splitting: Divide your screen into multiple windows.
  • Persistent Sessions: Reconnect to sessions after disconnection without losing state.
  • Multiple Views: View different sessions side-by-side.

Getting Started with Screen

Brief History and Development

Screen, developed by GNU, has been a staple among system administrators and power users for decades. It provides the basic functionality needed to manage multiple windows in a single session.

Installing Screen

To install Screen on Ubuntu or Debian:

sudo apt-get install screen

On Red Hat or CentOS:

sudo yum install screen

On Fedora:

sudo dnf install screen

02/04/2025   Linux Journal
Enhancing System Security and Efficiency through User and Group Management

Introduction

Linux, a powerhouse in the world of operating systems, is renowned for its robustness, security, and scalability. Central to these strengths is the effective management of users and groups, which ensures secure and efficient access to system resources. This guide delves into the intricacies of user and group management, providing a foundation for both newcomers and seasoned administrators to enhance their Linux system administration skills.

Understanding Users in Linux

In Linux, a user is anyone who interacts with the operating system, be it a human or a software agent. Users can be categorized into three types:

  1. Root User: Also known as the superuser, the root user has unfettered access to the system. This account can modify any file, run privileged commands, and has administrative rights over other user accounts.

  2. System Users: These accounts are created to run specific services such as web servers or database systems. Typically, these users do not have login capabilities and are used to segregate duties for security purposes.

  3. Regular Users: These are the typical accounts created for actual people using the system. They have more limited privileges compared to the root user, which can be adjusted through group memberships or permission changes.

Each user is uniquely identified by a User ID (UID). The UID for the root user is always 0, while UIDs for other users usually start from 1000 upwards by default.

Understanding Groups in Linux

A group in Linux is a collection of users who share certain privileges and access rights. Groups make it easier to manage permissions for a collection of users, rather than having to assign permissions individually.

  • Primary Group: When a user is created, they are automatically assigned a primary group. This group is typically named after the username and is used for setting the default permissions when the user creates new files or directories.
  • Secondary Groups: Users can be added to additional groups, allowing them more granular access to resources.

Groups are identified by a Group ID (GID), similar to how users are identified by UIDs.

User and Group Management Tools

Linux offers a suite of command-line tools for managing users and groups:

01/30/2025   Linux Journal
Debian Package Dependency Management: Handling Dependencies

Introduction

Debian-based Linux distributions, such as Ubuntu, Linux Mint, and Debian itself, rely on robust package management systems to install, update, and remove software efficiently. One of the most critical aspects of package management is handling dependencies—ensuring that all required libraries and packages are present for an application to function correctly.

Dependency management is crucial for maintaining system stability, avoiding broken packages, and ensuring software compatibility. This article explores how Debian handles package dependencies, how to manage them effectively, and how to troubleshoot common dependency-related issues.

Understanding Debian Package Management

Debian uses the .deb package format, which contains precompiled binaries, configuration files, and metadata describing the package, including its dependencies. The primary tools for handling Debian packages are:

  • dpkg: A low-level package manager used for installing, removing, and querying .deb packages.

  • APT (Advanced Package Tool): A high-level package management system that resolves dependencies automatically and fetches required packages from repositories.

Without proper dependency handling, installing a single package could become a nightmare of manually finding and installing supporting files. APT streamlines this process by automating dependency resolution.

How Dependencies Work in Debian

Dependencies ensure that an application has all the necessary libraries and components to function correctly. In Debian, dependencies are defined in the package’s control file. These dependencies are categorized as follows:

  • Depends: Mandatory dependencies required for the package to work.

  • Recommends: Strongly suggested dependencies that enhance functionality but are not mandatory.

  • Suggests: Optional packages that provide additional features.

  • Breaks: Indicates that a package is incompatible with certain versions of another package.

  • Conflicts: Prevents the installation of two incompatible packages.

  • Provides: Allows one package to act as a substitute for another (useful for virtual packages).

For example, if you attempt to install a software package using APT, it will automatically fetch and install all required dependencies based on the Depends field.

Managing Dependencies with APT

APT simplifies dependency management by automatically resolving and installing required packages. Some essential APT commands include:

  • Updating package lists: sudo apt update

01/28/2025   Linux Journal
Simplifying User Accounts and Permissions Management in Linux

Linux, renowned for its robustness and security, is a powerful multi-user operating system that allows multiple people to interact with the same system resources without interfering with each other. Proper management of user accounts and permissions is crucial to maintaining the security and efficiency of a Linux system. This article provides an exploration of how to effectively manage user accounts and permissions in Linux.

Understanding User Accounts in Linux

User accounts are essential for individual users to access and operate Linux systems. They help in resource allocation, setting privileges, and securing the system from unauthorized access. There are mainly two types of user accounts:

  • Root account: This is the superuser account with full access to all commands and files on a Linux system. The root account has the power to do anything, including tasks that can potentially harm the system, hence it should be used sparingly.
  • Regular user accounts: These accounts have more limited permissions, generally confined to the user's home directory. Permissions for these accounts are set in a way that protects the core functionalities of the system from unintended disruptions.

Additionally, Linux systems also include various system accounts that are used to run services such as web servers, databases, and more.

Creating and Managing User Accounts

Creating a user account in Linux can be accomplished with the useradd or adduser commands. The adduser command is more interactive and user-friendly than useradd.

Creating a new user

sudo adduser newusername

This command creates a new user account and its home directory with default configuration files.

Setting user attributes
  • Password: Set or change passwords using the passwd command.
  • Home directory: Specify a home directory at creation with useradd -d /home/newusername newusername.
  • Login shell: Define the default shell with useradd -s /bin/bash newusername.
Modifying and deleting user accounts
  • To modify an existing user, use usermod. For example, sudo usermod -s /bin/zsh username changes the user's default shell to zsh.
  • To delete a user, along with their home directory, use userdel -r username.

Understanding Linux Permissions

In Linux, every file and directory has associated access permissions which determine who can read, write, or execute them.

01/23/2025   Linux Journal
Exploring LXC Containerization for Ubuntu Servers

Introduction

In the world of modern software development and IT infrastructure, containerization has emerged as a transformative technology. It offers a way to package software into isolated environments, making it easier to deploy, scale, and manage applications. While Docker is the most popular containerization technology, there are other solutions that cater to different use cases and needs. One such solution is LXC (Linux Containers), which offers a more full-fledged approach to containerization, akin to lightweight virtual machines.

In this guide, we will explore how LXC works, how to set it up on Ubuntu Server, and how to leverage it for efficient and scalable containerization. Whether you're looking to run multiple isolated environments on a single server, or you want a lightweight alternative to virtualization, LXC can meet your needs. By the end of this article, you will have the knowledge to deploy, manage, and secure LXC containers on your Ubuntu Server setup.

What is LXC?

What are Linux Containers (LXC)?

LXC (Linux Containers) is an operating system-level virtualization technology that allows you to run multiple isolated Linux systems (containers) on a single host. Unlike traditional virtualization, which relies on hypervisors to emulate physical hardware for each virtual machine (VM), LXC containers share the host’s kernel while maintaining process and file system isolation. This makes LXC containers lightweight and efficient, with less overhead compared to VMs.

LXC offers a more traditional way of containerizing entire operating systems, as opposed to application-focused containerization solutions like Docker. While Docker focuses on packaging individual applications and their dependencies into containers, LXC provides a more complete environment that behaves like a full operating system.

01/21/2025   Linux Journal
Efficient Text Processing in Linux: Awk, Cut, Paste

Introduction

In the world of Linux, the command line is an incredibly powerful tool for managing and manipulating data. One of the most common tasks that Linux users face is processing and extracting information from text files. Whether it's log files, configuration files, or even data dumps, text processing tools allow users to handle these files efficiently and effectively.

Three of the most fundamental and versatile text-processing commands in Linux are awk, cut, and paste. These tools enable you to extract, modify, and combine data in a way that’s quick and highly customizable. While each of these tools has a distinct role, together they offer a robust toolkit for handling various types of text-based data. In this article, we will explore each of these tools, showcasing their capabilities and providing examples of how they can be used in day-to-day tasks.

The cut Command

The cut command is one of the simplest yet most useful text-processing tools in Linux. It allows users to extract sections from each line of input, based on delimiters or character positions. Whether you're working with tab-delimited data, CSV files, or any structured text data, cut can help you quickly extract specific fields or columns.

Definition and Purpose

The purpose of cut is to enable users to cut out specific parts of a file. It's highly useful for dealing with structured text like CSVs, where each line represents a record and the fields are separated by a delimiter (e.g., a comma or tab).

Basic Syntax and Usage

cut -d [delimiter] -f [fields] [file]

  • -d [delimiter]: This option specifies the delimiter, which is the character that separates fields in the text. By default, cut treats tabs as the delimiter.
  • -f [fields]: This option is used to specify which fields you want to extract. Fields are numbered starting from 1.
  • [file]: The name of the file you want to process.
Examples of Common Use Cases
  1. Extracting columns from a CSV file

Suppose you have a CSV file called data.csv with the following content:

Name,Age,Location Alice,30,New York Bob,25,San Francisco Charlie,35,Boston

To extract the "Name" and "Location" columns, you would use:

cut -d ',' -f 1,3 data.csv

This will output:

Name,Location Alice,New York Bob,San Francisco Charlie,Boston

01/16/2025   Linux Journal
How to Configure Network Interfaces with Netplan on Ubuntu

Netplan is a modern network configuration tool introduced in Ubuntu 17.10 and later adopted as the default for managing network interfaces in Ubuntu 18.04 and beyond. With its YAML-based configuration files, Netplan simplifies the process of managing complex network setups, providing a seamless interface to underlying tools like systemd-networkd and NetworkManager.

In this guide, we’ll walk you through the process of configuring network interfaces using Netplan, from understanding its core concepts to troubleshooting potential issues. By the end, you’ll be equipped to handle basic and advanced network configurations on Ubuntu systems.

Understanding Netplan

Netplan serves as a unified tool for network configuration, allowing administrators to manage networks using declarative YAML files. These configurations are applied by renderers like:

  • systemd-networkd: Ideal for server environments.

  • NetworkManager: Commonly used in desktop setups.

The key benefits of Netplan include:

  1. Simplicity: YAML-based syntax reduces complexity.

  2. Consistency: A single configuration file for all interfaces.

  3. Flexibility: Supports both simple and advanced networking scenarios like VLANs and bridges.

Prerequisites

Before diving into Netplan, ensure you have the following:

  • A supported Ubuntu system (18.04 or later).

  • Administrative privileges (sudo access).

  • Basic knowledge of network interfaces and YAML syntax.

Locating Netplan Configuration Files

Netplan configuration files are stored in /etc/netplan/. These files typically end with the .yaml extension and may include filenames like 01-netcfg.yaml or 50-cloud-init.yaml.

Important Tips:
  • Backup existing configurations: Before making changes, create a backup with the command:

    sudo cp /etc/netplan/01-netcfg.yaml /etc/netplan/01-netcfg.yaml.bak
  • YAML Syntax Rules: YAML is indentation-sensitive. Always use spaces (not tabs) for indentation.

Configuring Network Interfaces with Netplan

Here’s how you can configure different types of network interfaces using Netplan.

Step 1: Identify Network Interfaces

Before modifying configurations, identify available network interfaces using: