How Azure Security Center helps protect your servers with Web Application Firewall

Data di pubblicazione: 19 luglio, 2017

Principal Group Program Manager, Security Eng

Our adversaries have many tools available on the Internet for use in mounting cyberattacks. Many of these tools enable them to gain access and control of enterprise IT resources. In the meantime, security professionals are not always aware of the vulnerabilities built into the IT resources they are tasked to defend. Azure Security Center (ASC) can help bridge this gap.

This blog post is for IT and security professionals interested in using Azure Security Center (ASC) to detect and protect Azure-based resources from SQL injection attacks among others. The goal of this post is to 1) explain how this well-known code injection occurs and 2) illustrate how ASC detects and resolves this attack to secure your IT resources. 

Tools make SQL injection easy

Servers and applications are easy targets for cybercriminals. One well-known method for attacking data-driven applications is via SQL injection. SQL injection is an attack technique where malicious code is injected for execution which leads to un-intended database access. A popular tool attackers can use for malicious injection is sqlmap. By using sqlmap, it is easy to discover vulnerable SQL databases and expose their contents. An attacker only needs to provide the appropriate request headers to authenticate and discover the databases, their tables, and even dump the users and hashed passwords. Once the attacker has this data, their next step is to use brute force analysis on the exposed hashes, another built-in feature of the sqlmap tool to obtain the plaintext user credentials as depicted below.

Plaintext user credentials

Identifying risk with Azure Security Center

Azure Security Center (ASC), available on every subscription tier of Azure including free and trial subscriptions, can help identify connected IT assets with an HTTP endpoint. Additionally, ASC can automate the deployment of a Web Application Firewall (WAF) resource to help protect non-compliant resources, while pointing out detected malicious SQL injection attempts. The list of detections points to unprotected web servers where security remediation is needed. ASC scans virtual machines across an Azure subscription and makes recommendations to add Web Application Firewalls where applicable to at-risk resources.

Power BI 1Power BI 2

ASC then offers guidance through the process of deploying and configuring a Web Application Firewall for partner or first party solutions.

Create a new Web Application Firewall solution

Further guidance on tunneling IP traffic through the Web Application Firewall is also provided. This process provides an added layer of protection to the vulnerable web application.

Azure Security Center provides you with visibility, now that it’s been added to your resources, on the protections and detections including the Web Application Firewall.

Security alerts

Remedial actions with prevention

Configuring the WAF into prevention mode will prevent the sqlmap tool from accessing databases and tables it shouldn’t have access to. Thus, sqlmap can be prevented from even enumerating the type of database running on the backend, let alone traversing the databases for content. In prevention mode, the WAF prevents suspicious activity. ASC detects this and reports on the activity as it is blocked!

Prevention mode

Conclusion

Attack tools such as sqlmap are cheap and easily available. A “defense in depth” approach is critical to ensure applications are not vulnerable to SQL injection. Having visibility and control to detect and protect your resources against these attacks is crucial. ASC enables IT and security professionals to scan cloud-based resources for at-risk endpoints. Following recommendations by ASC, detection and protection can be achieved, helping organizations to meet their standards of information security compliance. While ASC is available on all subscription tiers of Azure, those on the Standard tiers can access a deeper level of insights, actions, and threat protection. If your enterprise requires a deep and granular level of cloud security, activate a free trial of Azure Standard to see how ASC can help your business.

This blog post compliments a deeper dive, step-by-step playbook. To learn more please read ASC Playbook: Protect Servers with Web App Firewall.

Have questions? Email us at AskCESec@microsoft.com.

- Hayden @hhainsworth