Category Archives: Azure Security

Azure Security Center: exports of alerts and recommendations to other solutions

Azure Security introduces an interesting feature that allows you to send security information generated by your environment to other solutions. This is done through a continuous export mechanism of alerts and recommendations to Azure Event Hubs or to Azure Monitor Log Analytics workspaces. This feature opens up new integration scenarios for Azure Security Center. This article describes how to use this feature and delves into its features.

Azure Security Center (ASC) carries out a continuous assessment of the environment and is able to provide the recommendations concerning the security of the environment. As described in this article you can customize the solution to meet your own security requirements and the recommendations that are generated. In the standard tier, these recommendations may not be limited to the Azure environment alone, but it will also be possible to contemplate hybrid environments and on-premises resources.

Standard Security Center also generates alert when potential security threats are detected on resources in your environment. ASC sets priorities, lists the alerts, provides the information you need to quickly investigate issues and provides recommendations on how to resolve attacks.

Azure Event Hubs is a streaming platform for big data and a service for the ingestion of events. Can receive and process millions of events per second. The data sent to a Event Hub can be transformed and stored using any real-time analytics provider or batch or storage adapters.

The new feature that was introduced in the Azure Security Center is called Continuos Export, supports enterprise scenarios and allows you to do the following:

  • Export to Azure Event Hubs to gain integration with third-party SIEMs and Azure Data Explorer.
  • Export to a Log Analytics workspace to have an integration with Azure Monitor, useful to better analyze data, use Alert rule, Microsoft Power BI and customized dashboards.
  • Export in a CSV file, for individual data exports (one shot).

The configuration is simple and can be carried out using the following procedure.

In Azure Security Center, you select the subscription for which you want to configure data export, and in the settings sidebar you select Continuos Export:

Figure 1 – Continuous export in ASC's subscription settings

In this case you chose to configure the export to a Log Analytics workspace. You can select which recommendations to export and their severity level. Also for security alerts you can choose for which level to export. Export creates an object, therefore, you should specify which resource group to place it in.. Finally, you will need to select the Log Analytics target workspace.

Figure 2 - Configuring parameters to make the Continuous Export

The link for integration with Azure Monitor provides the ability to automatically create Alert rule already pre-configured.

Figure 3 - Automatically create alert rules in Azure Monitor

By default these alert rules do not constitute the Action Group, therefore it is advisable to modify them to do a trigger to suit your needs.

These are the two default alert rules created:

Figure 4 – Default Alert rules of Azure Monitor

Alternatively, having gone into the recommendations and the ASC alerts in a workspace, you can configure in the Azure Monitor Alert rule customized based on Log Analytics query.

The security alerts and the ASC recommendations are stored in tables SecurityAlert and SecurityRecommendations of the workspace. The name of the Log Analytics solution that contains these tables is relative to the ASC tier, which can then be Security and Audit (standard tier) or SecurityCenterFree (tier free).

Figure 4 – Tables in Log Analytics

The configuration of Continuos Export towards Event Hubs is similar and it is the best methodology to incorporate the recommendations and the Azure Security Center alerts with third-party SIEM solutions. Following, shows the connectors for the main third-party SIEM solutions:

In Azure Sentinel is instead available Data connector , it is native to contemplate the Azure Security Center alerts.

To configure exports to Azure Data Explorer you can use the procedure in this Microsoft documentation.

Conclusions

With this new feature introduced in Azure Security Center, you can consolidate all the alerts and recommendations generated by the solution to other tools, opening up new possible integration scenarios even with third-party solutions. All this is made possible through an easily configurable mechanism, allowing you to be notified immediately and quickly take action. These aspects are crucial when dealing with security information.

Azure Security Center: how to customize the solution to meet your security requirements

Azure Security Center is a cloud solution that helps prevent, detect and respond to security threats that affect resources in the Azure environment and workloads in hybrid environments. By assigning a global score to your environment, you can assess your risk profile and act to take remediation action in order to improve the security posture. The solution is based on general recommendations, but in some cases it is appropriate to customize it to better contemplate your security policies. This article describes how you can introduce this level of customization in order to increase the value provided by Azure Security Center.

Using custom security policies

The default recommendations in the solution are derived from general industry best practices and specific regulatory standards.

Figure 1 – Standard score and recommendations in Azure Security Center

Recently was introduced the ability to add your own Initiatives custom, to receive recommendations if security policies specifically set for your environment are not met. The custom initiatives that are created are fully integrated into the solution and will be covered in Secure Score and in compliance dashboards.

To create a initiative you can follow the steps below:

Figure 2 – Starting the process of creating a custom initiative

Within the Initiatives you can include Azure Policies built into your solution or your own custom policies.

In the example below, theinitiative includes the following two policies:

  • A custom that prevents peering against a Hub network that is in a given resource group.
  • A bult-in that verifies that Network Security Groups are applied to all subnets.

Figure 3 – Creating a custom initiative

Following, you need to proceed with the assignment of theinitiative custom:

Figure 4 – Starting the assignment process

 

Figure 5 – Assigning the custom initiative

 

Figure 6 – Displaying the assigned custom initiative

The display of the recommendations in Security Center is not immediate, but currently it takes about 1 hour and you can see it in the following section:

Figure 7 - Custom initiative in the Regulatory Compliance section

 

Disable default security policy

Under certain circumstances it may be desirable to disable certain controls present by default in the Azure Security Center solution, as they are not appropriate for your environment and you do not want to unnecessarily generate the events. To do this, you can take the following steps::

Figure 8 - Access to the Security Center default policy

 

Figure 9 – Selecting the default Security Center policy assignment

 

Figure 10 – Disabling a specific policy that is present by default

 

Conclusions

Azure Security Center natively provides a series of controls to constantly check for conditions that are considered anomalous and can have a direct impact on the security of your environment. The ability to introduce a level of customization into your solution, makes it more flexible and allows you to verify and apply security compliance policies on a large scale that are specific to your environment. To improve security postures it is essential to evaluate the adoption of this solution and applying a good level of customization it greatly increases its value.

Azure Security: Best Practices to improve Security Posture

The tendency to have more frequently solutions in the cloud and hybrid architectures requires you to adopt high security standards for your environment. But how do you get effective cloud security for Azure and what best practices you should follow? This article summarizes the key practices that you should use in Azure to ensure a high level of security and improve security postures.

MFA activation and restrictions for administrative access

For users with administrative rights, authentication should be enabled using administrative Multi-factor Authentication (MFA). In this regard it is very interesting to evaluate passwordless authentication mechanisms that require that the password be replaced with something that you own more something that you are or that you know.

Microsoft currently offers three distinct passwordless authentication scenarios:

Azure Active Directory provides the ability to enable MFA mechanisms, including passwordless authentication. MFA mechanisms based on text messages are easier to bypass, so it's good to target different Multi-factor authentication mechanisms or passwordless.

Minimize the number of people and their time, for administrative access to Azure resources, it is a practice to be adopted because it reduces the possibility of an attacker obtaining administrative access or an authorized user inadvertently affecting a specific resource. To enable authorized users to perform administrative actions, you can offer just-in-time privileged access (JIT) Azure and Azure AD resources. To do this, the Azure Active Directory service is adopted (Azure AD) Privileged Identity Management (PIM) which allows you to manage, controlling and monitoring access to company resources is a good practice to take.

Another key aspect to consider is the use of secure and isolated workstations for sensitive roles. In this official Microsoft document you can get to obtain more details about it.

Segmentation and adoption of the Zero Trust model

The security model, definedZero trust and in contrast with the conventional models based on perimeter security, involves adopting an approach to micro-segmentation and the definition of granular perimeters in your network architecture. To contain security risks, it is good to adopt a clear and simple segmentation strategy, allowing stakeholders with a clear understanding, to facilitate and monitor effective management. It will also be useful to assign the necessary permissions and appropriate network controls.

In this regard, we report a reference design regarding the Azure administrative model:

Figure 1 – Reference Design – Azure Administration Model

The following illustration shows the typical Hub-Spoke network model, where theHub is a virtual network in Azure that serves as a point of connectivity to the on-premises network andSpoke are virtual networks running the peering with the Hub and can be used to isolate workloads.

Figure 2 – Reference Enterprise Design – Azure Network Security

Adoption of an appropriate "Firewall Strategy"

Adopting a firewall solution in the Azure environment to better protect and segregate network flows is now mandatory.

The choice may involve the adoption of:

  • Microsoft solutions fully integrated into the platform, such as Azure Firewall, flanked by Web App Firewall (WAF) of the Application Gateway, an application load balancer (OSI layer 7) for web traffic, that allows you to govern HTTP and HTTPS applications traffic. The Web Application Firewall Module (WAF) for web publications achieves an application protection, based on OWASP Core Rule sets rules. The WAF protects applications from vulnerabilities and common attacks , such as X-Site Scripting and SQL Injection attacks. These solutions are suitable for most of the scenarios and offer intrinsic high availability and scalability functionality as well as a simple configuration and centralized management.
  • Solutions provided by third-party vendors that are available in the Azure Marketplace. The Network Virtual Appliances (NVA's) are numerous, and can provide advanced features and provide continuity in the user experience compared to solutions already active in the on-premises environment. Typically the configuration of these solutions is more complex and the cost tends to be higher than Microsoft solutions.

Choosing a DDoS Mitigation Solution for critical applications

Very important is the protection of all critical applications from distributed denial-of-service cyberattacks (DDoS – Distributed Denial of Service). These attacks are aimed at deliberately to exhaust the resources of a given system that provides a service to clients, such as a website that is hosted on web servers, to the point that it will no longer be able to provide these services to those who require it in a legitimate way.

In Azure, DDoS protection is available in two different tiers: Basic oppure Standard.

Figure 3 - Comparison of the features available in different tiers for DDoS Protection

The protectionBasic is enabled by default in the Azure platform, which constantly monitors traffic and applies mitigations to the most common network attacks in real time. This tier provides the same level of protection adopted and tested by Microsoft's online services and is active for Azure Public IP addresses (Pv4 and IPv6). No configuration is required for the Basic tier.

Typology Azure DDoS ProtectionStandard provides additional mitigation features over the Basic tier, that are specifically optimized for resources located in Azure virtual networks. The protection policies are self-configured and are optimized by carrying out specific monitoring of network traffic and applying machine learning algorithms, that allow you to profile your application in the most appropriate and flexible way by studying the traffic generated. When the thresholds set in the DDoS policy are exceeded, the DDoS mitigation process is automatically started, which is suspended when it falls below the established traffic thresholds. These policies are applied to all public IP of Azure (IPv4) associated with resources present in the virtual network, like: virtual machines, Azure Load Balancer, Azure Application Gateway, Azure Firewall, VPN Gateway and Azure Service Fabric instances.

Azure Security Center Adoption

Azure Security Center is a cloud solution that helps prevent, detect and respond to security threats that affect the resources and workloads on hybrid environments. To improve the security posture of your Azure environment is essential to assess the adoption of this solution, it is offered in two different tiers:

  • Free tier. In this tier Azure Security Center is totally free and it will do a continuously assessment, providing recommendations relating to the security of the Azure environment.
  • Standard tier. Compared to tier free adds enhanced threat detection, using behavioral analysis and machine learning to identify zero-day attacks and exploits. Through machine learning techniques and through the creation of whitelist is possible to control the execution of applications to reduce exposure to network attacks and malware. Furthermore, the standard level adds the ability to perform in an integrated manner a Vulnerability Assessment for virtual machines in Azure. Azure Security Center Standard supports several resources including: VMs, Virtual machine scale sets, App Service, SQL servers, and Storage accounts.

Figure 4 - Comparison between the tiers of Azure Security Center

Azure Security Center assigns a score to your environment, useful for monitoring the risk profile and for try to constantly improve the security postures, applying remediation actions. Good rule is to verify on a regular basis (least monthly) the security score provided by Azure Security Center and program initiatives aimed at improving specific areas. Furthermore, it is recommended to carefully check the alert that Security Center Standard generates when it detects potential security threats on its resources. Security Center sets priorities, lists the alerts, provides the information needed to quickly examine the problems and provides advice on how to resolve any attacks.

Introduce security in development and release stages

The adoption of DevOps models to deploy Azure applications and services enable, as well as providing maximum agility, to obtain benefits in terms of security. In DevOps models can be engaged in development and management stages the teams dedicated to quality control and security throughout the application lifecycle. Using Infrastructure-as-Code processes(IaC) it is possible to define and monitor the compliance on a large scale.

Do not use legacy technologies

In Azure environment it is not recommended the adoption of classical Network Intrusion Detection System (NIDS) and Network Intrusion Prevention Systems (NIPS) since the platform is able to filter out malformed packets natively. The solutions NIDS / NIPS are generally based on outdated signature-based approaches that can be easily removed during attempted attacks and generally produce a high false positive rate.

Conclusions

Achieve a high level of security in Azure environments is a major challenge that needs to be won and it requires constant monitoring, review and updating of security postures. This article have been reported those that are considered the main best practices of security offered by a direct field experience, which it is always good to enrich them by taking further precautions.

Azure Security: how to do a Vulnerability Assessment using azure Security Center

Azure Security Center, the cloud solution that allows you to prevent, detect and respond to security threats affecting Azure resources and workloads in hybrid environments, recently enhanced with the ability to integrate a Vulnerability Assessment for Virtual Machines in Azure. This article explains how you can complete a vulnerability assessment process by using the Azure Security Center, examining the characteristics of the solution.

Vulnerability scanning included in Azure Security Center (ASC) is done through the solution Qualys, which is recognized as a leading tool for real-time identification of potential vulnerabilities in the systems. In order to use this feature you must adhere to the standard tier of Security Center, and in this case you will need to not incur additional licensing fees. The Standard tier also adds advanced threat detection (including threat intelligence), behavioral analysis, anomaly detection and security incidents and reports of conferral of threats.

If you wish to keep the tier free of ASC you can still make the deployment of solutions to perform a vulnerability assessment, which Qualys and Rapid7, but it is necessary to provide the management of the licensing costs, the distribution and configuration. For more details about the cost of Azure Security Center and for a comparison between the Free and the Standard tier, see the Microsoft's official documentation.

The most immediate and rapid method to scan for vulnerabilities in Azure is using the integrated solution Qualys in the Standard Tier of Azure Security Center. To enable it, simply go to the ASC Recommendations and select “Enable the built-in vulnerability assessment solution on virtual machines (powered by Qualys)“, come mostrato dall’immagine seguente:

Figure 1 - Recommendation of Azure Security Center to enable vulnerability assessment solution

Selecting this option Azure virtual machines are divided into the following categories:

  • Healthy resources: systems where the extension has been deployed to complete a vulnerability scan.
  • Unhealthy resources: machines where you can enable the extension to scan for vulnerabilities.
  • Not applicable resources: systems where the extension is not present and that it is not possible to enable it because they belong to the ASC tier free or because the operating system is among those not supported. Among the supported operating systems are: RHEL 6.7/7.6, Ubuntu 14.04/18.04, Centos 6.10/7/7.6, Oracle Linux 6.8/7.6, SUSE 12/15, and Debian 7/8.

Figure 2 - Enabling the solution

Selecting the machines of interest and pressing the button Remediate will be onboarded to the built-in Vulnerability Assessment solution. As a result, the specific extension will be installed on the systems and the first scan will be automatically started at the end of the installation.. The extesion is based on the Azure Virtual Machine agent and therefore runs in the Local Host context on Windows systems, and Root on Linux ones.

The names of the extension that will be present on the enabled systems are listed, for which the provider will always be Qualys:

  • Linux Machines: “LinuxAgent.AzureSecurityCenter”
  • Windows Machines: “WindowsAgent.AzureSecurityCenter”

As for extension updates, the same rules apply to other extensions, so the fewest versions of Qualys' scanner will be automatically deployed following an in-depth testing phase.. In some cases, you may need manual actions to complete the upgrade.

After the scan is complete, any vulnerabilities detected on the systems will be reported in the Recommendations by ASC.

Figure 3 – ASC notification reporting the presence of recommendations for intercepted vulnerabilities

Selecting the recommendation provides details of all vulnerabilities detected, severity and its status:

Figure 4 – List of detected security vulnerabilities

By selecting the single vulnerability you can see the details, potential impacts, remediation actions and affected systems.

Figure 5 – Information reported for each individual vulnerability detected

Conclusions

To strengthen the security posture of your environment you definitely should consider adopting Azure Security Center in the standard tier, that among the various functionality it allows to check that they are applied in a strict manner all safety criteria and allows to constantly monitor the compliance criteria. The inclusion in the solution of a vulnerability assessment tool, provided by Qualys, industry leader, adds further value to the solution, also be able to draw on the knowledge gained by this vendor in the discovery of vulnerabilities.