Overview
Tempesta FW is a unique open-source solution that combines web application firewall, load balancer, web accelerator, and DDoS mitigation in a single high-performance package. Unlike traditional WAFs that run in userspace, Tempesta FW is built directly into the Linux TCP/IP stack, enabling exceptional performance.
The hybrid architecture integrates seamlessly with Linux iptables and nftables, allowing multi-layer firewall rules that combine network-level filtering with application-layer inspection. This enables sophisticated protection scenarios like blocking IPs based on HTTP behavior while maintaining near-wire-speed performance.
Tempesta FW uses machine learning to dynamically monitor and predict backend server performance, enabling intelligent load balancing. The built-in Tempesta DB provides ultra-fast in-memory caching with NUMA-aware distribution and zero-copy interfaces for maximum throughput.
The Tempesta ecosystem now includes WebShield, an open-source automated bot protection system that detects and blocks bad bots (DDoS bots, scrapers, shopping bots, booking bots) using TLS and HTTP fingerprinting analysis on Tempesta FW access logs stored in ClickHouse. Together with an upcoming open-source volumetric DDoS protection solution, Tempesta is building a complete L3-L7 DDoS and bot protection stack.
Ratings Breakdown
Key Features
Kernel-Level Performance
Built directly into Linux TCP/IP stack, processing up to 1.8M HTTP requests per second - 3x faster than Nginx or HAProxy.
Multi-Layer DDoS Protection
Integrated protection against volumetric and application-layer DDoS attacks with rate limiting, JavaScript challenges, and adaptive QoS.
HTTP Tables
Extends Linux iptables/nftables for application-layer filtering, enabling rules that combine IP addresses with HTTP headers and content.
Intelligent Load Balancing
Machine learning-powered load balancing with persistent sessions, weighted round-robin, and rendezvous hashing strategies.
Web Acceleration
Built-in caching using Tempesta DB, an ultra-fast in-memory database with NUMA-aware distribution and SIMD optimizations.
High-Performance TLS
Tempesta TLS is 40-80% faster than Nginx/OpenSSL with 4x lower latency for TLS handshakes.
Bot Protection (WebShield)
Open-source automated bot protection via WebShield — detects and blocks DDoS bots, scrapers, shopping bots, and booking bots using TLS and HTTP fingerprint analysis on access logs stored in ClickHouse.
Volumetric DDoS Protection
Upcoming open-source volumetric DDoS protection solution, completing a full L3-L7 DDoS and bot mitigation stack when combined with Tempesta FW's application-layer defences and WebShield.
Native XDP Integration
Uses Linux XDP (eXpress Data Path) for early packet dropping, enabling efficient mitigation of volumetric attacks.
Pros & Cons
Pros
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Exceptional performance
Up to 1.8M requests per second, 3x faster than traditional reverse proxies, with 4x lower TLS latency.
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Completely free and open source
Full-featured WAF under GPLv2 license with no feature restrictions or usage limits.
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All-in-one solution
Combines WAF, load balancer, web accelerator, and DDoS mitigation in a single integrated package.
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Kernel-level integration
Deep Linux integration enables unique capabilities like HTTP Tables for multi-layer firewall rules.
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No external dependencies
Self-contained solution that replaces multiple components of your web infrastructure.
Cons
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Linux-only deployment
Requires Linux with kernel modifications; not available for Windows, containers, or cloud WAF-as-a-service.
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Complex setup
Kernel-level installation requires Linux expertise; not as simple as cloud WAF deployment.
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Beta status
Still in beta release; may not be suitable for risk-averse production environments.
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Limited community
Smaller community compared to ModSecurity or cloud WAFs; fewer resources and third-party integrations.
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No managed service option
Must self-host and manage; no cloud-managed offering available.
Pricing
Pricing model: Free (open source) + professional services
Open Source
Full-featured open-source WAF under GPLv2 license
- Complete WAF functionality
- DDoS mitigation
- Load balancing
- Web acceleration with caching
- Community support via GitHub
Professional Services
Expert installation, configuration, and optimization services
- Professional installation and setup
- Configuration optimization
- OS and kernel tuning
- Performance optimization
- Custom development
Our Verdict
Tempesta FW represents a fundamentally different approach to web application security. By building the WAF directly into the Linux kernel, it achieves performance levels that traditional userspace solutions simply cannot match. For organizations with the technical expertise to deploy and manage it, Tempesta FW offers exceptional value.
The all-in-one architecture is compelling - replacing separate WAF, load balancer, cache, and DDoS mitigation components with a single integrated solution. The addition of WebShield for automated bot protection and an upcoming open-source volumetric DDoS solution further strengthens the ecosystem into a full L3-L7 security stack. However, this comes with trade-offs: kernel-level deployment is more complex, the project is still in beta, and the smaller community means fewer resources for troubleshooting.
Our verdict: Best choice for performance-critical Linux deployments where teams have the expertise to manage kernel-level software. Not recommended for teams seeking simplicity or managed services.
CVE Coverage
Tempesta FW can detect and block attacks matching 81K+ known CVEs based on its supported rule sets.
Coverage by Attack Type
Latest Blockable CVEs
| CVE | Severity |
|---|---|
| CVE-2026-4510 | MEDIUM |
| CVE-2026-4161 | MEDIUM |
| CVE-2026-4087 | MEDIUM |
| CVE-2026-4086 | MEDIUM |
| CVE-2026-4084 | MEDIUM |
| CVE-2026-4077 | MEDIUM |
| CVE-2026-4072 | MEDIUM |
| CVE-2026-4069 | MEDIUM |
| CVE-2026-4067 | MEDIUM |
| CVE-2026-4022 | MEDIUM |
Frequently Asked Questions
How does Tempesta FW compare to ModSecurity?
ModSecurity is a mature, widely-deployed WAF module for Apache, Nginx, and IIS. Tempesta FW takes a different approach by building directly into the Linux kernel. Tempesta FW offers significantly better performance (3x faster) but requires more expertise to deploy. ModSecurity has a larger community and more rule sets available, while Tempesta FW provides integrated load balancing and caching that ModSecurity lacks.
Can Tempesta FW run in containers or Kubernetes?
Tempesta FW requires direct kernel access and modifications, making it incompatible with standard containerized deployments. It cannot run inside Docker containers or as a Kubernetes pod. For containerized environments, consider using Tempesta FW on the host level to protect containerized applications, or choose a cloud-native WAF solution.
Is Tempesta FW production-ready?
Tempesta FW is currently in beta status. While it is functional and used in production by some organizations, the beta designation means there may be breaking changes and less stability than mature WAF solutions. Evaluate carefully for mission-critical deployments and consider starting with non-production workloads.
What Linux distributions does Tempesta FW support?
Tempesta FW provides packages and installation scripts for major Linux distributions. It requires a compatible kernel version with specific patches. Check the official documentation for supported distributions and kernel versions, as these requirements are updated with each release.
Ready to try Tempesta FW?
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