Virtualization Security – A Complete Guide


Virtualization Security – A Complete Guide- Despite the fact that virtualization is a fifty-year-old concept, it has progressed to the point where it can now accommodate sophisticated applications in development. Virtual Machines (VMs) are used by half of all servers, and IDC projects that by 2024, VMs will be used by over 70% of all computer workloads. As the number of virtualization components grows and the virtualized environment grows, the key challenge is how to maintain secure security and integrity levels. Here’s a quick rundown of some of the distinctions, concerns, challenges, and hazards that virtualization brings with it. This document also contains some suggestions for ensuring that the network is secure to the needed level.

Virtualization provides security benefits

The following security advantages will result from introducing virtualization into the environment:

  • It is feasible to share systems with a properly configured network without needing to share important data or information. One of the most important security benefits of a virtual environment is its flexibility.
  • A centralised storage system is used in virtualized environments to prevent important data loss in the event of a lost device or when the system is deliberately hacked.
    In the event that a threat is discovered, VMs and apps may be effectively segregated to reduce the risk of additional attacks.
  • By lowering the number of hardware in an environment, virtualization increases physical security. A virtualized environment means fewer data centres because the hardware is reduced.
    In the event of an incursion, server virtualization allows servers to revert to their original condition. This improves incident response because an event can be tracked before, during, and after an assault.
  • The hypervisor software is straightforward and compact. As a result, the hypervisor has a reduced attack surface. The attack surface is smaller, which means there are fewer vulnerabilities.
  • Access control is more restricted for network and system administrators. By splitting duties, the system’s efficiency can be increased. Someone might be in charge of VMs within the network’s perimeters, while someone else is in charge of VMs in the DMZ, for example. Individual administrators can be assigned to Linux servers while others are assigned to Windows servers, depending on how the system is configured.

I’ve used the phrases “if set up or configured adequately” several times. This is done to demonstrate virtualization’s complexity. As a result, in order to reap the benefits, it must be properly guarded.

Security challenges and risks

Now we may go on to some of the obstacles, hazards, and other pertinent topics that affect virtualization.

Guests and Hosts can share files

  • When a file-sharing service is employed, a hacked visitor can remotely view, alter, and/or change a host file. The malicious visitor has the ability to change the directory structure of files being transferred.
  • When APIs are utilised for programming, or when guests and hosts share files via clipboard sharing, there is a greater risk of significant defects in the area, potentially jeopardising the entire infrastructure.


  • When the ‘host’ hypervisor is compromised, it affects the virtual machines tied to it. A hypervisor’s default configuration is ineffective in providing complete security from threats and attacks.
  • Because hypervisors are compact, have minimal exposure surface areas, and control everything, they also put the system at risk by giving a single point of failure. A single hypervisor assault can jeopardise the entire ecosystem.
  • Administrators can alter and share security credentials at their leisure because hypervisors manage nearly everything. Because the administrators hold the keys to the kingdom, it’s tough to figure out who did what.


  • When you reverse a snapshot, you lose any current configurations or modifications. If the security policy is changed, for example, the platforms may become accessible. To make matters worse, audit logs are frequently lost, making it impossible to track changes. Meeting the required compliance requirements can be difficult without all of these.
  • New photos or snapshots may be a cause for concern, much as physical hard drives, snapshots, and images might include PII (Personally Identifiable Information) and passwords, and previously stored snapshots with undetected malware can be loaded at a later date to cause havoc.

Storage in a network

  • Because they are clear text protocols, iSCSI and Fibre Channel are vulnerable to man-in-the-middle attacks. Sniffing tools can also be used by attackers to monitor or track storage traffic for later use.

Separation of duties and administrative access

  • Network administrators handle network management completely in an ideal physical network, while server administrators handle server management. Both the two administrators play a part in security personnel. In a virtualized system, however, network and server administration can be delegated from the same management platform. This presents a unique issue in terms of ensuring appropriate division of roles. Virtualization solutions, in most situations, give users complete control over all virtual infrastructure activities. This usually occurs when a system has been hacked but the default settings have never been altered.

Synchronisation of Time

  • Tasks can run early or late due to a mix of VM clock drift and regular clock drift. As a result, any precision in the logs is lost. If forensic investigation becomes necessary in the future, there will be inadequate data due to faulty tracking.


  • Multiple virtual machines (VMs) running on the same host are segregated so that they cannot be exploited to attack other virtual machines. Despite their separation, the partitions share CPU, memory, and bandwidth. As a result, if a danger, such as a virus, causes a partition to consume a large quantity of one, both, or all of the resources, other partitions may suffer a denial of service assault.


  • VM traffic must be routed from the host to a firewall in order for VLANs to be employed. The procedure may result in latency or complex networking, both of which might reduce the overall network’s performance.
  • On a VLAN, communication between different VMs isn’t secure and can’t be monitored. If the VMS and the VLAN are on the same VLAN, malware spreads like wildfire, and it is impossible to stop it from spreading from one VM to the next.

Common attacks on virtualization

The three most frequent virtualization-related attacks are listed below:

Attack on the Service (DoS)

Hypervisors are likely to be fully shut down in the event of a successful denial of service assault, and black hats will likely construct a backdoor to access the system at their leisure.

Interception of host traffic

File tracking, paging, system calls, memory monitoring, and disc activity tracking can all be done through loopholes or weakness points in the hypervisor.

VM Jumping

A user can almost smoothly jump from one VM to another if a security weakness, such as a hole, exists in the supervisor. Unauthorized users from another VM can then change or steal data.


The majority of the present virtualized security concerns can be addressed in part by utilising existing technology, people, and processes. The fundamental flaw is that they are unable to secure the virtual fabric, which is made up of virtual switches, hypervisors, and management systems. A look at some of the classic techniques of provide virtualized security, as well as some of their flaws, is provided below.


Some security employees force communication between regular system firewalls and VMS in order to monitor log traffic and provide feedback to virtual machines. Due to the fact that virtualization is a new technology, firewalls do not provide a well-tailored infrastructure to address security concerns. Before virtualization was implemented and accepted in data centres and organisations, there were firewalls. As a result, because current security threats to virtualization appear to be sophisticated for the system, the pre-installed management solutions are unable to handle them. As a result of these setbacks, manual administrations may be implemented, which may result in errors owing to human error.

VMs assigned to physical NICs per Host should be reduced

This strategy decreases the number of virtual machines that must be installed on a single host and assigns each one a physical NIC. This is one of the most cost-effective ways to secure the company, but it excludes the benefits of virtualization and other cost-cutting measures.

Intrusion Detection in a Network

Devices do not perform effectively when there are several VMs on a single host. This is due to the fact that IPS/IDS systems are unable to monitor network traffic between VMs effectively. When the programme is relocated, data is also unavailable.


For both virtualized and non-virtualized booth setups, VLANs are widely employed. It becomes more difficult to manage the intricacies associated with access control lists as the number of VLANs grows. As a result, maintaining compatibility between virtualized and non-virtualized components of the environment becomes increasingly complex.


A complete copy of anti-virus software is mapped on each VM when using an agent-based anti-virus strategy. It’s a safe solution, but it’ll cost a lot of money to load anti-virus copies throughout the entire environment’s virtual machines. Because the software is huge, it consumes more computer resources. As a result, it has an adverse effect on memory, CPU, and storage, as well as a reduction in performance.

Despite the disadvantages highlighted above, a larger percentage of businesses still use traditional network security techniques. With advances in technology and IT infrastructure, virtualized environments are very dynamic and develop at a quick pace. To acquire the best protection for such an unpredictable environment, it’s best to combine the finest features of today’s security strategy with the virtualized environment guidelines stated below.

For a secure virtualized environment, best practises and guidelines are provided

Securing the network

  • By disconnecting any idle NIC, you may close any gaps in the system.
  • Set up logging and time synchronisation, place things in place to govern users and groups, and set file permissions on the host platform that connects guests and hypervisors to a physical network to secure it.
  • To protect IP connection between two hosts, use authentication and encryption on each packet.
  • To eliminate any interference from man-in-the-middle attacks, remove the use of default self-signed verifications.
  • Place virtual switches in a promiscuous mode to watch traffic and allow MAC address filtering to prevent MAC spoofing attacks.
  • Ensure that all traffic, including traffic between the hypervisor and the host using SSL, traffic between clients and hosts, and traffic between the hypervisor and management systems, is encrypted.

Recovery following a disaster

  • Have a good change management system in place so that the main site and backup sites are as similar as feasible.
  • The PEN test and auditing for your DR site and the main site should be done separately, but with the same frequency and importance.
  • Logging and other documents retrieved from the DR site should be considered as seriously as those retrieved from the primary site.
  • At the disaster recovery location, make sure your production firewall is operational and secure. If the firewall is disabled or until an event occurs, perform regular audits at the primary site.
  • Replicas of sensitive data or information should be encrypted and preserved properly.
    Make a one-of-a-kind storage system

Responsibilities are separated, and the administrator has access to everything

  • Server administrators should be given unique access to the servers they are responsible for.
    Admins should be able to build new virtual machines but not edit those that already exist.
    Unless there is a compelling reason for two or more guest OSs to share credentials, each guest OS should be granted a unique authentication.
  • Security professionals have discovered that the broader the virtualized environment, the easier it is to transfer responsibilities across functions, contrary to popular belief. An administrator cannot handle all aspects of management on their own.

Safeguarding your computer

The four effective measures to eradicate illegal and unsecured virtualization in an environment are listed below.

Outline the policy for permitted usage.

Define which approvals are required and under what conditions virtualization software can be implemented.

Reduce the number of virtual machines (VMs) compared to the total number of users.

Virtual machines (VMs) aren’t required by every user. On business laptops and desktops, restrict the installation of freely available software.

Implement virtualization-assisted security policies.

Ascertain that our system does not contradict with existing virtualization platforms in terms of security policies.

Create a Secure VM build library

Set up a repository of VM builds to save security software, updates, and configuration information that users can readily access and re-use as needed.

Vulnerability Assessment

  • Virtual machines should not be stored on management networks linked to hypervisors.
    On physical servers, using processing-intensive screensavers can cause the processor required to service the VMs to become overburdened.
  • Only construct virtual machines (VMs) if they’re needed. Black hats may be able to gain access to the environment through unused VMs.
  • VMs should be able to readily use the kennel or host resources, such as storage networks.
  • All unnecessary interfaces, such as USB ports on virtual machines, should be disabled.
  • Encrypt data between the Host and the Virtual Machine.
  • Using VLANs within a single VM switch, traffic segmentation can be accomplished.
  • I have a detailed framework in place for planning, deploying, patching, and backing up virtual machines.
  • Set up different physical servers or security domains for workloads with different levels of trust.
  • Dormant virtual machines should be examined on a regular basis, or access should be blocked.

System of Governance

  • Secure connection between the host and management systems by enabling SSH, SSL, or IPSec protocols. Man-in-the-middle attacks, data loss, and eavesdropping are all prevented by doing so.
  • Installing a single unifying security policy and management system for both virtual and physical environments is required to avoid the need for double-checking reports or analysis.
  • Separate database and administration servers are recommended.
  • Access to the management server should be restricted. It shouldn’t be possible to access it from every workstation.

Securing Hypervisors

  • Updates and fixes should be installed as soon as they are available. Hypervisor vulnerabilities can be mitigated by implementing good patch management.
  • Remove services like file sharing that you don’t need.
  • The logs from the hypervisor should be examined on a regular basis to identify any system flaws.
  • For hypervisor functionalities, employ a multi-factor authentication approach.
  • The hypervisor’s administration interface should not be accessible over the network.

Remote Access

  • Only a restricted number of authorised management system IP addresses should be used for remote access management.
  • Every remote access account should have a strong password policy. A two-factor authentication or the usage of a one-time password is recommended for high-risk locations or attack-prone environments.
  • Encryption should be used when sending data or information to management systems.


  • Backups should never be performed using root accounts.
  • In a virtualized environment, disc backups are just as necessary as they are in a physical one.
  • Once a week, perform a full system backup and take regular or daily OS and data backups.
  • Encrypt all data transported over the network to a disaster recovery site.


Virtualization is a dynamic and rapidly evolving technology that has posed new hurdles for most security companies. As a result, current techniques and processes are unable to adequately secure the virtual environment and all of its components. This is due to the fact that virtualization is a mix of a physical network and a new logical or virtual environment. Additional safeguards and considerations must be implemented quickly to guarantee a robust security posture. The company must plan and prepare ahead of time for how to handle the new virtual infrastructure and all of its components from a security standpoint. Security should be a top priority for virtualization, not a last-minute consideration.

Jennifer Thomas
Jennifer Thomas is the Co-founder and Chief Business Development Officer at Cybers Guards. Prior to that, She was responsible for leading its Cyber Security Practice and Cyber Security Operations Center, which provided managed security services.