Web applications are a major attack surface for cybercriminals today. Customer portals, e-commerce systems, administrative panels, APIs – each of these is a potential entry point if not properly secured. The Web Application Firewall (WAF) is a layer of protection that stands between the Internet and the application and filters malicious traffic. The Barracuda WAF is distinguished by its flexible delivery model and particularly good fit for cloud environments.
Key findings
- WAF protects web applications from OWASP Top 10 attacks – SQLi, XSS, CSRF and more
- Barracuda WAF is available as a physical appliance, virtual appliance and SaaS model
- The platform offers automatic signature updates and zero-day protection
- Barracuda also protects APIs – a key attack vector in modern architectures
- The solution supports compliance with PCI DSS and other regulations
Table of contents
- Why do web applications need dedicated protection?
- What is a WAF and how is it different from a network firewall?
- Barracuda WAF architecture – deployment models
- Protection from OWASP Top 10
- API protection – growing importance
- Bot mitigation – distinguishing humans from automatons
- DDoS protection in Barracuda WAF.
- Compliance and reporting
- FAQ
- Summary
Why do web applications need dedicated protection?
A traditional network firewall operates at the packet and connection level – it decides whether traffic on a given port and protocol is allowed. It does not analyze HTTP content, does not understand application logic and does not distinguish between a legitimate SQL request and an SQL Injection attempt. For an attacker who sends a malicious payload hidden in a legitimate HTTP request to port 443, a traditional firewall is invisible.
Web applications also have unique vulnerabilities due to their architecture and business logic. OWASP (Open Web Application Security Project) regularly publishes a list of the Top 10 most dangerous classes of application vulnerabilities – and it is these attacks that WAF is designed to detect and block.
What is a WAF and how is it different from a network firewall?
WAF (Web Application Firewall) is a specialized firewall that operates at the Layer 7 (application) level of the OSI model. It analyzes the content of HTTP/HTTPS requests, understands the structure of a web application and can distinguish legitimate requests from application attacks.
WAF analyzes HTTP headers, URL parameters, POST content, cookies and other elements of a web request to look for signatures of known attacks, anomalies in request structure and behaviors that suggest malicious intent. Unlike IPS/IDS, which is more general, WAF is specialized for web applications and their specific threats.
Barracuda WAF architecture – deployment models
Barracuda WAF is available in several delivery models, which is one of its key advantages. It is available as a physical appliance (for data centers with hardware requirements), as a virtual machine (VMware, Hyper-V, KVM), as a cloud native solution on AWS, Azure and Google Cloud, and as a SaaS service (Barracuda WAF-as-a-Service).
The WAF-as-a-Service model is particularly attractive for organizations that want to protect cloud applications without managing their own infrastructure. All inspection takes place in the Barracuda cloud, and the application is protected without any changes to its infrastructure.
Protection from OWASP Top 10
Barracuda WAF includes protection for all categories of attacks on the OWASP Top 10 list. SQL Injection – attempts to manipulate databases through malicious SQL queries in request parameters. Cross-Site Scripting (XSS) – injection of malicious executable scripts through the victim’s browser. Broken Authentication – detection of session hijacking attempts and credentials stuffing. Insecure Direct Object References, Security Misconfiguration, Sensitive Data Exposure and more.
Protection is implemented through a combination of signatures (for known attacks), heuristic analysis (for variants of known attacks) and machine learning (for new attack patterns).
API protection – growing importance
Modern web applications increasingly rely on APIs for communication between components. Attacks on APIs are the fastest growing category of web attacks – attackers have discovered that APIs are often not covered by the same security policies as web interfaces.
Barracuda WAF protects APIs by validating JSON and XML schemas, restricting allowed HTTP methods per endpoint, detecting anomalies in API calls and enforcing authentication and authorization policies at the level of each endpoint.
Bot mitigation – distinguishing humans from automatons
Much of the web traffic comes from bots – both legitimate (search engine crawlers) and malicious (data scrapers, attacking automatons, bots trying out stolen login credentials). Barracuda WAF distinguishes human traffic from bots through behavioral analysis (timing, navigation patterns), JavaScript and CAPTCHA verification for suspicious requests, and lists of known malicious bots updated in real time.
DDoS protection in Barracuda WAF.
Barracuda WAF offers protection against application-level (Layer 7) DDoS attacks – that is, attacks that, instead of flooding the network with packets, send a large number of seemingly legitimate HTTP requests that overload the application. Such attacks are much more difficult to repel with traditional network measures.
The platform uses per-IP and per-session request limiting, geographic blocking of traffic and moving suspicious traffic for verification, protecting application availability even during an active attack.
Compliance and reporting
Barracuda WAF supports compliance with PCI DSS requirements for protecting web applications that handle payment card data. It generates detailed reports on traffic, blocked attacks and security events that can be used for both ongoing monitoring and documentation for auditors.
FAQ
Does the Barracuda WAF work with any web application? Yes – WAF acts as a proxy in front of the application and is agnostic to the technology in which the application is written.
Doesn’t WAF slow down applications? The Barracuda WAF is optimized for minimal impact on latency. With proper sizing, the performance impact is imperceptible to users.
How does the Barracuda WAF deal with false positives? The platform offers a learning mode that analyzes normal application traffic and builds a baseline, reducing false positives. Policies can also be manually tuned.
Does the Barracuda WAF support your own organization’s SSL certificates? Yes – WAF implements SSL termination and can support client certificates or use its own.
Summary
Barracuda Web Application Firewall is comprehensive web application protection in a flexible delivery model tailored for cloud and hybrid environments. OWASP Top 10 protection, dedicated API protection, bot mitigation and built-in compliance capabilities make the Barracuda WAF a solid application security foundation for organizations of all sizes.
