A Web Application Firewall (WAF) is a security appliance that sits between users and web servers, filtering malicious HTTP requests. WAFs detect and block SQL injection, XSS, DDoS, and credential stuffing attacks in real time. Used by security engineers, DevOps, and site reliability roles across finance, e-commerce, and SaaS. Salary band: $110–160k for mid-level WAF specialists. Takes 3–4 months to proficiency with Cloudflare, AWS WAF, or ModSecurity experience.
A Web Application Firewall (WAF) is a security appliance or service that monitors, filters, and blocks malicious HTTP and HTTPS traffic destined for web applications. WAFs sit at the edge (either cloud-hosted or on-premise) and inspect request payloads for attacks like SQL injection, cross-site scripting (XSS), command injection, and DDoS patterns before traffic reaches your application servers. WAFs use signature-based detection, behavioral analysis, and machine learning to classify requests as benign or hostile. They're deployed by every major web property (banks, e-commerce platforms, SaaS) and are often required by compliance frameworks (PCI-DSS, SOC 2).
| Region | Junior | Mid | Senior |
|---|---|---|---|
| USA | $85k | $140k | $200k |
| UK | $50k | $90k | $130k |
| EU | $55k | $95k | $140k |
| CANADA | $80k | $130k | $185k |
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