#linuxsecurity

[sentientcitysurvival]

Basic Linux Security (Updated 2025)

Install Unattended Upgrades and enable the "unattended-upgrades" service.

Install ClamAV and enable "clamav-freshclam" service.

Install and run Lynis to audit your OS.

Use the "last -20" command to see the last 20 users that have been on the system.

Install UFW and enable the service.

Check your repo sources (eg; /etc/apt/).

Check the /etc/passwd and /etc/shadow lists for any unusual accounts.

User the finger command to check on activity summaries.

Check /var/logs for unusual activity.

Use "ps -aux | grep TERM" or "ps -ef | grep TERM" to check for suspicious ongoing processes.

Check for failed sudo attempts with "grep "NOT in sudoers" /var/log/auth.log.

Check journalctl for system messages.

Check to make sure rsyslog is running with "sudo systemctl status rsyslog" (or "sudo service rsyslog status") and if it's not enable with "sudo systemctl enable rsyslog".

Perform an nmap scan on your machine/network.

Use netstat to check for unusual network activity.

Use various security apps to test you machine and network.

Change your config files for various services (ssh, apache2, etc) to non-standard configurations.

Disabled guest accounts.

Double up on ssh security by requiring both keys and passwords.

Check your package manager for any install suspicious apps (keyloggers, cleaners, etc).

Use Rootkit Scanners (chkrootkit, rkhunter).

Double SSH Security (Key + Password).

Disabled Guest Accounts.

Enabled Software Limiters (Fail2Ban, AppArmor).

Verify System Integrity via fsck.

Utilize ngrep/other networking apps to monitor traffic.

Utilize common honeypot software (endlessh).

Create new system-launch subroutines via crontab or shell scripts.

Ensure System Backups are Enabled (rsnapshot).

Check for suspicious kernel modules with "lsmod"

[dollar2host]

Linux: The ultimate defense in your digital arsenal. Win every battle, protect every byte.

[osintelligence]

https://bit.ly/3pdoaNg - 🔒 AhnLab Security Emergency Response Center (ASEC) has discovered a series of attacks involving the Tsunami DDoS Bot being installed on poorly managed Linux SSH servers, alongside other malware strains such as ShellBot, XMRig CoinMiner, and Log Cleaner. #CyberSecurity #DDoS #Malware 🎯 The primary attack vectors are DDoS bots or CoinMiners, most commonly found on improperly secured Linux SSH servers. The attacks frequently involve the attacker logging in via dictionary attacks and installing DDoS Bots and XMRig CoinMiner. #CyberAttack #InfoSec #SSH 🤖 Tsunami, also known as Kaiten, is a DDoS bot that operates as an IRC bot. Its source code is publicly available, making it a popular choice among threat actors, particularly for attacks against IoT devices and Linux servers. #Botnet #IoTSecurity #LinuxSecurity ⚠️ The threat actor typically installs a backdoor SSH account after logging in, allowing them to regain access to the system and perform various malicious activities such as installing different malware and stealing information. #ThreatIntel #Backdoor 💻 The analysis of malware involved in the attack includes Tsunami (or Kaiten), ShellBot, Log Cleaner, Privilege Escalation Malware, and XMRig CoinMiner. These strains have different functionalities, from DDoS attacks, to log cleaning, privilege escalation, and cryptocurrency mining. #MalwareAnalysis #CyberThreats 🛡️ To secure systems from such attacks, administrators should use complex passwords, change them regularly, update to the latest patches, restrict external access, and use up-to-date security programs.

[techyeco]

Best free VPNs for Linux

🌐 Looking for privacy solutions for your Linux system? Discover the top free VPNs for Linux to enhance your security and protect your online data. 🔒 👉 Read the full guide here: https://techyeco.com/free-vpn-for-linux/ #LinuxSecurity #VPNSolutions #TechPrivacy

[virtualizationhowto]

Openscap: Open Source Vulnerability and Compliance Scanner

Openscap: Open Source Vulnerability and Compliance Scanner @vexpert #vmwarecommunities #100daysofhomelab #homelab #OpenSCAPintroduction #OpenSCAPscannerinstallation #SecurityContentAutomationProtocol #Linuxsecurity

Open-source security tools are not only cost-effective, they are also very powerful. OpenSCAP is a robust line of defense in achieving and maintaining system security compliance. It delivers many features, including for the community and enterprise businesses. Table of contentsWhat is OpenSCAP?Diving Deeper into the SCAP Security GuideCustomizing OpenSCAP with Your Own Content FilesOpenSCAP…

[swift-screen]

Installieren und Konfigurieren der CSF Firewall unter AlmaLinux 9

[sciedithub-services]

Completed #linux project named as read more Completed :The Open 3D Foundation Welcomes Epic Games as a Premier Member to Unleash the Creativity of Artists Everywhere

[freeonlinecoursesudemy]

Linux Security and Hardening, The Practical Security Guide

Requirements - Little knowledge about any Unix Operating System RAM 8GB , CPU Two Cores,Oracle Virtual BOX,CentOS IOS image Description  This course covers foundation security concepts and guidelines that can help Linux system administrators keep their Linux servers safe. It also takes you step-by-step though hardening measures. Explore some of the security weaknesses of the Linux operating system, and learn how to protect against those weaknesses. Learn about ways to prevent attackers from breaking into your systems when they have physical access to your machine. Plus, learn how to secure the various account types on a Linux system, enforce strong passwords, configure the firewall in Linux, and more. The Following topics include: ·         What makes Linux secure? ·         Physical security concepts ·         Encrypting new and existing devices ·         Account and network security ·         Linux firewall fundamentals ·         File system security ·         File and directory permissions - Linux Security Demos IDS and Fail2BAN 1-what is tripwire? 2-Install and Configure Tripwire IDS on CentOS 7? 3-What is Fail2BAN? 4-How to Setup and configure Fail2Ban on CentOS 7? Who this course is for: - System Administrator, Database Administrator, DevOps developer Read the full article

[linuxtechlab]

NMAP command (short for Network Mapper) is an open-source network security tool & is the best port scanner for your server/network. Nmap command is widely used for auditing the network security & also for the penetration testing of your networks.

[technologydumps-blog]

On this article I will explain few things that help us preparing our system for implementing some particular service. Here we should go through some topic to make a server secure and workable over network.