Security Considerations for Azure Linux & Windows Subsystem for Linux Users

Azure Linux is a public computing platform developed by Microsoft that businesses can use for tasks like app development, analytics, virtual computing, networking, storage, and more. Linux uses Azure more frequently than Windows since the server can run large workloads. Windows Subsystem for Linux (WSL) permits developers to run Linux directly on Windows and is a lighter alternative to Virtual Machines.

It would be best to stay aware of the network security threats and cybersecurity vulnerabilities that Azure Linux and WSL have yet to mitigate, such as firewalls that bypass security or hackers gaining unauthorized access to root privileges. Understanding the network security issues will make using Azure security tools much easier, as you will know what solutions to apply to the problem. This article will evaluate Azure Linux and WSL security, how they react to various cybersecurity trends, and the best tips and practices to use when securing them.

What Is Azure Linux? 

Azure Linux is a cloud-hosted Operating System (OS) based on the open-source Linux OS. You can host your preferred Linux OS and images through the community-supported distribution Azure Linux. There are various OS options to choose from on Azure Marketplace as well.  

Deploy and scale web apps through this cost-effective and straightforward platform. You only pay for features you want to use, and Azure Linux adjusts to your needs by monitoring resources, making the service a helpful, affordable choice.

More and more people are using Azure for Linux as the years continue. In 2016, only twenty-five percent of the platform had Linux, followed by forty percent in 2017 and fifty percent in 2018, and Linux surpassed Windows in use in 2019. Linux now dominates most of Microsoft’s cloud platforms, as developers can benefit from Linux’s open-source licensing.

Azure has a team of over 3,500 cybersecurity experts facilitated in state-of-the-art data centers worldwide. The highly secure platform offers various third-party solutions to users and can strengthen data and network security. Microsoft continuously analyzes billions of web pages, emails, device updates, and authentications to help detect network security threats faster.  

What is Windows Subsystem for Linux (WSL)? 

Windows Subsystem for Linux (WSL) is a Microsoft-developed network security toolkit that allows users to run Linux natively on Windows without needing a dual-boot setup. Project Astoria provided all of the technology WSL needed during its release in 2016. Several Linux distros, Windows 10, and other servers can get support from WSL. You can download Linux distributions like Ubuntu, Debian, Gentoo, or Fedora from the app store and install WSL on your Windows PC.

WSL gives developers an unbeatable Linux experience even when using Windows as their primary OS. Developers can run Linux apps on Windows, a much simpler task than doing so with dual-boot or Virtual Machines (VM). Most laptops and PCs come with Windows preinstalled, so WSL is an excellent tool for learning both systems more efficiently.

WSL comes in two versions: WSL1 and WSL2, the more upgraded version from 2019. Both use advanced virtualization technology to run a Linux kernel within a Virtual Machine. However, WSL2 has more features to increase performance and add full system call compatibility.  

According to studies from Stack Overflow and others, over fifteen percent of developers use WSL, which is active in over 3.5 million active devices monthly.

Notable Azure Linux And WSL Security Issues 

Here is a list of cybersecurity vulnerabilities to be aware of on Azure Linux and WSL:

OMIGOD 

In September 2021, Microsoft’s Open Management Infrastructure (OMI) project discovered the vulnerability OMIGOD (as dubbed by Wiz), where the OMI agent gets deployed secretly. Failure to apply security patching grants attackers access to root privileges to execute ill-natured code distantly. Hackers can encrypt your files and deny you access until you pay a ransom. Sixty-five percent of Azure Linux users still face this network security threat, so run OMI version 1.6.8.1 or later to stay safe.

FabricScape Bug 

The Service Fabric (SF) platform hosts millions of business apps, including Azure Linux. Discovered in January 2022, FabricScape allows cybercriminals to access root privileges, take control of the host node, and overwrite files with harmful content. Fortunately, security professionals have mitigated FabricScape attacks in network security. Though such exploits in cybersecurity are no longer a concern, it would be wise to upgrade to the latest SF version as soon as possible and ensure that you have enabled automatic updates on Linux clusters.

WSL-Based Malware 

Researchers detected more than 100 WSL-based malware in the past few years. Most network security issues spy on users’ information and secretly install malicious modules. Telegram is a malware service that grants unauthorized access to attackers, as this malware has low detection rates that hackers capitalize on to inflict harm on unsuspecting Linux users. Be sure to inspect your Linux system and be alert for suspicious activity to prevent facing malware risks. 

Windows 10 Firewall Bypass 

WSL2 can bypass security in the Windows 10 Firewall and all other configured rules, unlike WSL1. WSL can still reach the internet when using a Virtual Private Network (VPN), which could expose your system to various network security threats. Fortunately, there are commands to block connections.

Security Implications That WSL Users Should Be Aware Of: How Secure is WSL?  

WSL users debate whether using the platform creates unwarranted network security issues. Besides noting cybersecurity vulnerabilities, we must also understand how running sensitive apps on WSL can be less secure than running them on Windows or Linux. 

Additionally, sensitive data theft occurs when running Linux apps on WSL, and anti-virus programs cannot always detect such network security threats. However, WSL is still as secure as any other app running on your Windows OS. Ensure your OS is threat-free, and you will not need to be concerned about facing WSL compromise.

Best Practices for Securing Azure Linux & WSL 

Software developers work around the clock to mitigate WSL and Azure Linux cybersecurity vulnerabilities. Here are a few best practices to utilize when keeping your server secure:

• Achieve an advanced data and network security level by using third-party Azure security tools that enhance monitoring and remediation capabilities.
• Update your OS to the latest version, and do the same with all apps you include in custom virtual images.
• Implement a business continuity and disaster recovery strategy to keep your data safe during unprecedented outages. 
• Use Azure Backup to facilitate recovery if your data gets corrupted due to application errors or bugs. 
• Use Azure Disk Encryption to make your data unreadable to hackers who may access your system without authorization. 
• Use sophisticated anti-malware from trusted vendors like Microsoft, Symantec, or Kaspersky to protect your system from network security threats. 
• Use Azure Key Vault to store your keys securely and ensure only authorized people can access the vault. 
• Use Just-In-Time (JIT) VM access to restrict inbound traffic through management ports. 
• Set up your network security groups with rules that govern your screen traffic flow so you can take care of cybersecurity vulnerabilities quickly.
• Take advantage of the Azure security center to identify and quickly mitigate network security threats. The security center combines all security alerts, enabling you to see messages and respond accordingly. You can also access a detailed account of network security issues and recommendations for alleviating them. Microsoft investigates the threats reported on Azure Security Center and analyzes the frequency of attacks in network security so the servers can notify users immediately.
• Use Azure Sentinel to collect data regarding security activities for analysis and threat hunting. 
• Install Microsoft Defender for Endpoint (MDE), which utilizes behavioral sensors to collect and analyze behavioral signals from the OS. Whenever MDE detects a threat, the system alerts a Microsoft analyst, who analyzes the risks and offers appropriate remediation steps. Typically, you must disconnect the compromised devices and maintain a connection to MDE so they can monitor your server.

Microsoft has a wide range of network security toolkits and features to ensure you stay safe while using Azure Linux and Windows Subsystem for Linux. Coupled with third-party data and network security tools, you can mitigate attacks.

Our Final Thoughts on Security Considerations for Azure Linux & Windows Subsystem for Linux Users

Azure Linux and WSL are precious tools that revolutionize how developers work with Linux. You can access the OS through the cloud or a Windows computer instead of a Linux desktop, but you would open up more attack surfaces for malicious hackers. Hopefully, these tips and best practices can assist you in mitigating cybersecurity vulnerabilities in your system so that you do not need to be concerned about attacks in network security that could lead to compromise.