What Is Virtual Patching & Its Role in Vulnerability Mitigation

Key Takeaways

• Virtual patching provides immediate security by blocking exploit attempts without modifying the original code.
• Unlike live patching, virtual patching is a temporary security measure, using firewalls, IPS, and security monitoring tools to mitigate risks until an official patch is applied.
• Unpatched systems face serious threats, including cyberattacks, data breaches, compliance violations, and operational disruptions.
• TuxCare’s KernelCare Enterprise helps businesses secure their Linux infrastructure without reboots or downtime.

There are many different ways to improve upon traditional patching, so it’s easy to get confused about how each patching approach works. In the past, we’ve looked at traditional patching vs live patching, but we’ve also received questions about virtual patching and how it stacks up.

In this blog post, we’ll explore what virtual patching is, differences between live patching and virtual patching, describe the situations in which each is most useful, and help you decide which is the best choice for your own environment.

What Is Virtual Patching?

Virtual patching is the process of blocking a known exploit at the network level. It operates at the firewall level, either locally to protect a single system or at the perimeter firewall level to protect the systems behind the firewall.

Virtual patching specifically targets remote-only exploitable vulnerabilities, so if a malicious actor compromises the remote login of a valid user and then deploys a local-only exploit to gain privilege elevation, virtual patching would not protect against it. In fact, virtual patching does not actually “patch” anything – it simply prevents the attacker from remotely exploiting some vulnerabilities.

The Importance of Virtual Patching

Sometimes the patches are not immediately available for vulnerabilities, like zero-day vulnerabilities. In such cases, virtual patching becomes an essential security measure to protect the system against possible exploits.

Protects Against Zero-Day Attacks

A zero-day vulnerability is one that is exposed to attackers even before a vendor has an official fix. Virtual patching provides immediate risk mitigation, blocking exploits before the vendor’s official patch is released. This helps minimize exposure and reduces the attack surface.

Secures Legacy Systems

Older software and legacy systems that no longer receive official support lack security updates. Virtual patching allows businesses to maintain security without modifying outdated applications, extending their usability while mitigating risks.

Helps Maintain Compliance

Many industries require timely vulnerability remediation to meet compliance standards like PCI DSS, HIPAA, and GDPR. Virtual patching ensures businesses stay compliant by proactively addressing security flaws when immediate patching isn’t possible.

Lowers the Risk of Exploit-Based Attacks

Cybercriminals exploit known vulnerabilities using automated scanning and attack scripts. Virtual patching disrupts such tactics by blocking exploit attempts before they reach the system, thereby reducing the odds of breaches and data theft.

How Does Virtual Patching Work?

Virtual patching acts as a protective layer that detects and blocks exploit attempts before they reach a vulnerable system. It doesn’t modify the original code but instead enforces security policies at the network or application level.

This is achieved through tools like Web Application Firewalls (WAFs), Intrusion Prevention Systems (IPS), and Security Monitoring Solutions, which analyze traffic for malicious patterns. When an exploit attempt is detected, the system blocks or filters the request, effectively patching the vulnerability without touching the underlying software. This real-time defense is crucial for zero-day threats, legacy systems, and high-availability environments.

Key Challenges of Patching That Businesses Experience

Patching is critical for security, but many businesses struggle with downtime, compatibility issues, and delayed updates. In enterprise environments, where uptime is essential, these challenges slow patch deployment and leave systems vulnerable to cyberattacks. Below are the top challenges organizations face when patching their infrastructure:

Service Disruptions

Traditional patching often requires system reboots or scheduled maintenance, leading to downtime. In critical infrastructure and always-on environments, frequent disruptions are not an option, making traditional patching impractical. This is where live patching becomes a game-changer, allowing security updates without interrupting operations.

Limited Patch Availability

Vendors don’t always release patches immediately, especially for zero-day vulnerabilities, legacy software, or end-of-life (EOL) software & products. This leaves businesses without an official fix, forcing them to rely on alternative security solutions like virtual patching or extended support.

Resource Constraints

Effective patch management requires skilled IT staff, security expertise, and the proper infrastructure. However, small and mid-sized businesses (SMBs) often lack dedicated resources, making it difficult to deploy patches promptly. This delay increases security risks and leaves systems vulnerable to attacks.

Compliance Pressure

Regulatory standards mandate timely patching, but operational challenges can cause delays, leading to non-compliance. Failing to meet these requirements puts businesses at risk of fines, legal consequences, and reputational damage.

The Risks of Unpatched IT Infrastructures

Unpatched vulnerabilities invite cyberattacks, data breaches, and compliance violations. Attackers actively exploit known weaknesses, leading to financial losses, operational disruptions, and reputational damage. Without timely patching, organizations remain exposed to escalating threats. Below are the biggest risks of leaving IT systems unpatched:

Increased Exposure to Cyberattacks

Hackers actively look out for unpatched vulnerabilities in the systems to launch ransomware, malware, and exploit-based attacks. Delayed patching creates an easy entry point, allowing attackers to infiltrate systems and compromise sensitive data.

Data Breaches

Exploited vulnerabilities can lead to data theft, unauthorized access, and intellectual property loss. Breaches result in hefty financial penalties, legal consequences, and reputational damage, affecting long-term business viability.

Compliance Violations

Timely patching is essential to maintain compliance with industry standards and regulations. Failure to address vulnerabilities can lead to non-compliance, legal actions, and heavy fines, putting the organization at risk.

Operational Downtime

Cyberattacks exploiting unpatched systems can disrupt operations, corrupt data, or render critical services unavailable. Recovering from an attack is costly, requiring incident response, forensic analysis, and downtime mitigation efforts.

Loss of Customer Trust

A security breach caused by unpatched vulnerabilities erodes trust and damages brand reputation. Customers expect businesses to protect their data, and security failures can drive them to competitors.

Live Patching vs Virtual Patching: Is There A Difference?

Live patching is the process of patching a running application directly as it is running, in memory. The files on the disk are not touched, but every instance of the application or library that is currently running will be updated to reflect the latest patched version.

If you restart the application, it will restart as what is currently on disk and any live patches will be reapplied by your live patching application after it launches. TuxCare’s KernelCare Enterprise solution is a perfect example of this.

The main benefit is that patching becomes a non-disruptive action, and patches can therefore be applied more often – enabling you to respond faster to new threats.

Live patching can, when implemented correctly, protect a system from many different types of vulnerabilities, irrespective of such vulnerabilities being remotely exploitable or local-only. This protects against vulnerability-chaining, that is, when a local-only exploit is deployed after another vulnerability allows remote access (or even through a compromised valid remote access).

Now let’s take a look at virtual patching. Virtual patching relies on known network “signatures” or profiles, and can thus be defeated if the attacker adds additional encryption layers or changes some part of the known-attack path. It’s best considered an additional layer inside the firewall rather than a true patching solution, similar to what application-level firewalls do.

However, if the attacker manages to bypass the firewall, then the protection will not work at all. In fact, if multiple systems rely on that firewall for protection against vulnerabilities, then bypassing the firewall (either through encryption, remote access, or changing the attack signature) means that all those systems will be at risk.

When it blocks an attack, to an outside actor it will simply appear as if it has not worked, so that actor might assume the system being targeted is not vulnerable or has indeed been patched (hence the name). As with live patching, at no point are any files updated.

Final Thoughts On Live Patching & Virtual Patching

Additional layers of security are always desirable. That’s why we have firewalls, patching, anti-virus, and a series of other tools to elevate the security profile of a system or environment – but virtual patching does not replace live patching. Each class of patching mechanism has different goals and operates at different levels in an IT infrastructure.

If you’re concerned about keeping systems running securely and want to close the most amount of security issues, either locally or remotely exploitable, then rebootless patching is the best solution for your situation. TuxCare’s KernelCare Enterprise ensures your Linux systems stay protected with automated rebootless patching, eliminating risks without service disruptions.

If, on top of that, you want to add virtual patching, consider it as a network level protection – not system-level patching.

Summary

Article Name

What Is Virtual Patching & Its Role in Vulnerability Mitigation

Description

Virtual patching blocks security threats without downtime. Learn how it mitigates vulnerabilities, protects systems, and ensures compliance without code changes.

Author

Joao Correia

Publisher Name

TuxCare

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