Virtual machines and security gaps: risks and protection

The widespread adoption of the cloud has made virtual machines and security vulnerabilities two sides of the same coin. What was once an innovative approach is now the standard: virtually every organization, large or small, has some of its systems running on virtualized infrastructures, whether on AWS, Azure, GCP, or other providers, or in its own data center.

This technological leap has brought enormous advantages in cost, speed, and flexibility , but it has also opened up a gigantic attack surface that many companies are still not controlling. Orphaned VMs, identities with excessive permissions, poorly protected hypervisors, or users unaware of the risks of virtualization are a perfect recipe for serious cybersecurity incidents.

From the arrival of AWS to the explosion of virtualization

When Amazon launched its first public cloud services, such as Simple Storage Service (S3) and Elastic Compute Cloud (EC2) , a paradigm shift occurred in how IT resources were consumed. Suddenly, setting up servers, storing large volumes of data, or scaling an application no longer depended on purchasing expensive hardware and waiting weeks, but could be done in minutes from a web panel.

With this revolution, the concept of "setting up a server" was transformed into creating a virtual machine on demand . Companies began migrating applications, databases, and critical services to the cloud, and today it's difficult to find an organization that doesn't use at least one virtualized service or isn't planning that transition.

Many companies already operate with a fully cloud-based model, while others maintain hybrid or multicloud environments , combining resources across AWS, Azure, GCP, and on-premises servers. This technological mosaic is very powerful, but it also poses a significant security challenge, especially when there isn't a unified view of everything that has been deployed.

Meanwhile, virtualization isn't limited to the public cloud: hypervisors allow the creation of virtual machines on local hardware , virtualization of storage, networking, and data, and the delivery of highly available services. All of this increases the complexity of environments and requires security to address multiple layers simultaneously.

Proliferation of virtual machines: the “deploy and decay” problem

One of the clearest side effects of the cloud model is that providers have made it almost trivial . A developer, data analyst, or machine learning engineer can deploy an instance in a matter of minutes, with just a few clicks. The problem is that when they no longer need it, there's almost never the same urgency to shut it down or properly decommission it.

Many companies experience what is known as uncontrolled proliferation: fleets of virtual machines scattered across multiple clouds, projects, subscriptions, and accounts, often without an up-to-date inventory. Furthermore, only a minority of organizations claim to have complete visibility into their cloud footprint, leaving a significant percentage of assets unaccounted for.

These VMs often don't receive operating system updates , aren't monitored, or maintain access policies that haven't been reviewed since they were created. The typical scenario is a VM set up for a temporary project, granted broader permissions than recommended "to speed things up," and then left running, forgotten, and with excessive privileges.

The consequence is that these workloads can become silent entry points for attackers. Unlike more visible errors, such as misconfigured storage buckets or APIs exposed to the internet, internal abuse of a virtual machine typically generates fewer obvious signals, so it can go undetected for much longer.

Reports such as those from the Cloud Security Alliance indicate that misconfiguration and poor change control are now among the top threats in the cloud, closely followed by identity and access management (IAM) issues. This is all exacerbated when organizations lack clear processes for the VM lifecycle: creation, usage, permissions review, and secure decommissioning.

Identities, permissions, and lateral movement in the cloud

In modern cloud environments, virtually everything revolves around identity. Every virtual machine, role, container, or service has an assigned identity and associated permissions to access other resources. In fact, in many organizations, workload (non-human) identities far outnumber those of actual users.

When a VM is provisioned for a specific task—for example, a data analytics or machine learning lab—the common temptation is to grant it broad permissions on storage, databases, or other services , because applying the principle of least privilege takes time. That VM ends up being used for the project, but it remains active, with a powerful identity and is rarely monitored.

If an attacker manages to compromise that instance, they have an ideal foothold. From there, they can move laterally within the virtual network , connect to other VMs, explore internal databases, or interact with storage buckets. In many deployments, east-west traffic (between machines within the same network) is not as segmented as it should be because fine-level microsegmentation is perceived as "too complex."

In hybrid environments, things get even more complex. A cloud VM linked to identities synchronized with local directories can use that trust relationship to access on-premises resources: file shares , internal applications, databases, or critical components of the corporate infrastructure. The transition from cloud to on-premises is facilitated through these federated identity chains.

In addition to all this, many traditional security solutions focus on user computers, traditional servers, or network perimeters, but they don't correlate in real time what the VM is doing with what its identity is doing in the rest of the environment. The result is that a compromised machine can appear to be acting normally at the system level while, at the permissions level, it's performing massive accesses to sensitive data without raising immediate suspicion.

Real-life cases of virtual machine abuse and vulnerabilities

Practical examples help illustrate the severity of the problem. In one reported case, a malicious actor compromised multiple AWS EC2 instances and moved between them using internal Remote Desktop Protocol (RDP) . They organized hundreds of gigabytes of stolen data, distributing it across different VMs, and ultimately released ransomware within that cloud environment.

In that campaign, monitoring was in place, but the automated response was not properly configured , so the alerts did not lead to effective containment actions. The ransomware ended up executing and affecting a significant volume of assets despite anomalous activity having been detected beforehand.

In another case documented by Microsoft, attackers leveraged compromised Azure accounts to launch short-lived virtual machines , using them as disposable infrastructure for various types of attacks. Because the traffic originated from legitimate Azure IP addresses, many security alerts were treated as false positives and ignored.

There have also been some unusual situations where the platform itself reacted to potential abuse. Following suspicious activity related to the use of a global administrator and the creation of machine learning resources in Azure (with high compute and bandwidth costs), the provider blocked the creation of new virtual machines and restricted resizing except for reserved instances. Although the compromised resources were removed, the impact on the ability to operate VMs was significant until the incident was resolved.

These incidents demonstrate that the fraudulent use of virtual machines can have direct consequences for costs, availability, and service continuity , beyond the data theft itself. Furthermore, they underscore the importance of having robust auditing, support, and incident response processes that connect technical issues with business decisions.

Economic, regulatory, and detection time risks

When a security breach exploits a virtual machine, the repercussions extend far beyond the technical aspects. Recent studies show that a significant proportion of SMEs suffer financial penalties following a cyberattack, due to non-compliance with regulatory frameworks or the leakage of sensitive customer and employee data.

Standards such as NIST 800-53, PCI DSS 4.0, and other industry standards are becoming increasingly explicit in requiring controls over cloud workloads and their associated identities. Securing the servers that store critical information is no longer sufficient; the focus has clearly shifted to the identity layer and how permissions for VMs and other virtual resources are regulated, assigned, and monitored.

On the other hand, reports on the cost of data breaches reveal that a significant proportion of incidents affect information distributed across multiple environments : public clouds, private clouds, and on-premises systems. This patchwork approach easily lengthens the attacker's dwell time (the time between intrusion and detection), increasing both the potential damage and the final cost of the breach.

When organizations lack deep visibility into what is happening in their virtual infrastructure , they often find out about intrusions through external signals: a customer complaint, a supplier detecting anomalies, a warning from a third party… By then, the attacker may have spent weeks or months moving around the environment, exfiltrating information and preparing sabotage or extortion actions.

All of this confirms that, in the context of virtual machines, security cannot be limited to "installing antivirus software" or "closing ports": it requires comprehensive and continuous risk management , including processes, technology, training, and corporate governance.

Advantages of virtual machines: why we still need them

The fact that VMs pose risks doesn't mean they aren't essential. In fact, they remain one of the pillars of modern infrastructure for several compelling reasons that are worth keeping in mind to understand why their use has become so widespread.

First, they allow for extreme optimization of hardware resources . A single physical server typically has more capacity than a single application requires; by running multiple virtual machines on the same host, CPU, memory, and storage are better utilized, reducing waste and improving the return on investment in infrastructure.

Secondly, they offer robust isolation between environments . The hypervisor acts as an intermediary between the physical hardware, the host operating system, and the guest operating systems, defining what they can see and how they can interact with each other. If one VM is compromised, the typical design makes the impact on the other instances and the host much smaller than in less segmented models.

The third major advantage is scalability and flexibility . Virtual machines can be created, modified, and shut down quickly, which perfectly aligns with dynamic workloads and the cloud philosophy. This allows you to handle traffic spikes, launch new services, or run tests without constantly purchasing and installing new hardware.

Finally, its use directly contributes to cost reduction . Before mass virtualization, acquiring physical servers involved high investments, long delivery times, and limited scalability. With VMs, organizations can adjust their resource consumption to actual demand, pay as needed, simplify energy and hardware maintenance, and focus efforts on the business and application layers.

Hypervisors and security gap analysis in virtualized environments

Behind every virtual machine is a hypervisor, and this component is critical from a cybersecurity perspective. A hypervisor is the software that manages the creation, execution, and isolation of VMs , controlling access to the underlying hardware, network and storage resources, and many other sensitive functions.

Modern virtualization encompasses multiple layers: hardware, operating systems, storage, network, and data . Each of these layers introduces potential attack vectors that can compromise both the VMs and the hypervisor itself. A vulnerability in this component can allow an attacker to escape from one virtual machine and access others, or even take control of the entire host.

Therefore, it is essential to have a clear methodology for analyzing security gaps specifically applied to hypervisor environments. This type of guide addresses issues such as reviewing underlying services, network segregation, controlling access to the management console, protecting shared storage, and preventing unauthorized data access.

These analyses pay particular attention to service level agreements (SLAs), the confidentiality and integrity of resources , and how the different vertical layers of the virtualized infrastructure communicate with each other. The goal is to build a defense-in-depth strategy, where a failure in one layer does not compromise the entire environment.

Furthermore, it's important to consider that hypervisors can be targeted by cybercriminals seeking to isolate or control the management plane by exploiting vulnerabilities or misconfigurations. Without a well-designed architecture and adequate controls, containing an attack targeting this central component of the virtual ecosystem will be extremely difficult.

Key best practices for securing virtual machines

To reduce security gaps associated with virtual machines, it is essential to implement a set of best practices that encompass both technical and organizational aspects. A first set of measures involves properly managing identities and access : applying strong password policies, enabling multi-factor authentication, limiting permissions based on roles, and regularly reviewing accounts with elevated privileges.

Another crucial aspect is keeping VMs updated with the latest security patches . This includes not only the guest operating system but also the applications and services running within it. Ignoring these updates opens the door to known exploits that attackers systematically use.

Protecting data within virtual machines requires using encryption techniques for both data at rest and in transit. Tools like full disk encryption help mitigate the impact of unauthorized physical access or hardware theft, while communication encryption reduces the risk of espionage or data manipulation on the network.

Furthermore, it is advisable to combine these controls with monitoring and intrusion detection solutions specifically designed for virtualized environments. This allows for the identification of anomalous runtime behavior, the correlation of events between different VMs, and the generation of automatic responses (such as isolation or shutdown) when signs of compromise are detected.

All of this must be integrated into a global policy that covers the entire life cycle of virtual machines: from their provisioning, through their daily operation, to their secure retirement, including controlled disk erasure and revocation of associated identities.

The internal digital divide and its impact on VM security

Not all risks stem from technology; a significant portion arises from the digital divide within companies themselves . This divide isn't simply about having or not having internet access, but rather the difference between organizations and teams well-trained in digital tools and cybersecurity, and others that continue to operate with outdated knowledge and practices.

In the business world, the digital divide has several dimensions. On the one hand, there's the technological dimension : companies with modern infrastructure versus those still relying on outdated systems that don't adequately support virtualization or the cloud. On the other hand, there's the knowledge dimension : workforces that don't receive sufficient training in best practices for security and technology management.

There is also a strategic dimension: many organizations lack clear plans for integrating digitalization and cybersecurity into their processes. This leads to decisions about creating VMs, assigning permissions, or choosing cloud providers being made without a comprehensive view of risks and objectives.

The direct consequence is an increase in threats: constant cyberattacks on outdated systems , loss of information due to a lack of adequate backups, less competitiveness compared to companies that automate processes and use the cloud securely, and a greater probability of human errors due to lack of knowledge.

Closing this gap requires investing in appropriate technological infrastructure, migrating to the cloud when it makes sense, promoting automation, and, above all, training staff to understand the risks and protective measures . Without this human component, any virtual machine security strategy falls short.

Managed services and technology partners to protect virtualization

Many SMEs and organizations with small IT teams face a dual challenge: maintaining daily operations while simultaneously securing increasingly complex virtual and cloud environments . In these cases, relying on specialized providers and managed services is, in practice, one of the most sensible options.

Managed cloud services typically include a dedicated team of experts who monitor and manage the virtual infrastructure , apply security patches, review configurations, and continuously watch for potential suspicious behavior. This approach allows companies to offload some of the technical burden and focus on their core business.

Providers with experience in virtual machine security, industrial networks and hybrid environments can offer tailored solutions : from the design of segmented and secure networks, to the implementation of firewalls, intrusion detection systems, threat intelligence platforms or backup and data recovery strategies adapted to the industrial or corporate context.

Furthermore, these partners typically provide 24/7 support and continuous monitoring , enabling them to react quickly to incidents and maintain a high level of availability for VMs. This is especially critical in sectors where system downtime results in significant financial losses or major operational risks.

Working with these types of partners does not exempt the company from its responsibility in matters of security, but it does help to overcome internal limitations of knowledge, personnel and time, and to implement good practices that might be difficult to adopt alone.

The combination of a robust virtualization strategy, clear identity and access policies, ongoing training, and expert support transforms virtual machines into powerful business allies rather than blind spots where the most painful breaches occur. Only when an organization fully understands how these VMs are created, managed, secured, and retired, and has the right culture and tools, can it truly enjoy the agility of the cloud without constantly teetering on the edge of risk.