Spotlight
PAGE: https://alison.com/course/network-server-security-protecting-the-server-and-client-computers-revised
PROMISE: Map legacy Windows and Linux security gaps to current network fundamentals.
WHO: Sysadmins maintaining mixed Windows and Linux estates who need foundational network security knowledge.
WHYNOW: Bridging the knowledge gap between legacy Windows maintenance and modern X11 security concepts.
DESC: In this free online network server security course learn with Alison about the fundamentals of security within a computer network.
BEFORE: Legacy Windows and Linux systems coexist with undefined security boundaries.
BEFORE: Firewall configurations are ad hoc and do not account for mixed protocol needs.
BEFORE: Security teams lack a common vocabulary for threats across different OS environments.
AFTER: Isolation methods are applied to separate legacy Windows assets from modern Linux nodes.
AFTER: Firewall types are correctly matched to the security requirements of both OS types.
AFTER: The team uses a shared framework to identify and describe network threats.
GAIN: A clear taxonomy of firewall types to secure both Windows and Linux endpoints.
GAIN: Practical isolation methods to protect legacy systems within a modern network.
GAIN: The ability to identify malware and rootkits that target mixed operating environments.
STEP: You cannot distinguish which firewall rules block malware on legacy Windows servers. || List the different firewall types || Apply the correct firewall classification to both Windows and Linux nodes to close attack vectors.
STEP: Your mixed environment lacks defined isolation between the old Windows clients and the XWayland stack. || Discuss different network access methods and isolation methods || Configure network segmentation so legacy systems are isolated from the newer X11 infrastructure.
STEP: You suspect rootkits on the Linux side but do not know which protocols signal the intrusion. || Describe different protocols for network security || Monitor specific security protocols to detect anomalies in the X.Org and XWayland traffic flows.
STEP: Updates are delayed because you cannot identify the specific threats exploiting the unpatched servers. || Identify different threats to your computer, and/or network such as malware, worms, rootkits etc || Prioritize patching X.Org and XWayland based on the specific threat landscape of your mixed environment.
NOTFOR: Readers needing step-by-step terminal commands to update X.Org or XWayland binaries.
NOTFOR: Teams that require advanced hardening guides specifically for X11 configuration files.
FACT: Average duration: 1.5-3 Hours (Contains Video)
FACT: CPD-accredited certificate available
FACT: Beginner level
COVERS: Having completed this course you will be able to:
COVERS: List the different firewall types
COVERS: Discuss different network access methods and isolation methods
COVERS: Describe different protocols for network security
COVERS: Identify different threats to your computer, and/or network such as malware, worms, rootkits etc
COVERS: Explain how you can protect your computer and/or network from different threats
COVERS: Describe how to use Internet Explorers security features
COVERS: Programming
COVERS: Technology
COVERS: Course Overview
COVERS: About This Course
COVERS: Course Description
MODULE: Understanding Network Security || Firewalls | Network Access and Isolation Protection | Protocol and Wireless Network Security
MODULE: Protecting the Server and Client || Protecting Your Computer from Malware | Protecting the Client Computer, Email and Server | Securing Internet Explorer
What you are probably seeing
Admins see new X.Org server 21.1.25 and XWayland 24.1.14 in package managers. The changelog highlights fixes for disclosed security gaps.
The current versions on the server remain unpatched, leaving the display infrastructure exposed to known issues until the update is installed.
Why it happens
Attackers target the display server because it manages sensitive input, output, and window management for user sessions.
Unpatched versions allow malicious actors to exploit these known flaws, potentially compromising the underlying operating system or exfiltrating data.
What changed recently
Step by step
1. Open the system terminal and run the command to update the package index list.
2. Run the package manager install command to download and install X.Org 21.1.25 and XWayland 24.1.14.
3. Check the log output to confirm that the installation of both components finished without errors.
4. Restart the X server or the system to apply the changes to the display stack.
5. Verify the running version strings using the query tools to ensure the new patched releases are active.
Ways to go further
Start here: Network Server Security – Protecting the Server and Client Computers For when you maintain legacy Windows environments alongside Linux. Open the free course on Alison ↗
Affiliate links: CHEAPUNO may earn a commission if you buy through them, at no extra cost to you.
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