Imperva's RASP is pushed as the "next step" beyond WAF. But I'm not seeing the value for the cost and complexity.
A well-tuned WAF with the right signatures should catch the vast majority of app-layer attacks. RASP promises deeper context, but in practice:
* Adds significant overhead to each application instance.
* Creates another data silo separate from your existing telemetry.
* The "zero-day" protection claims are vague. It's still signature and behavior-based.
For the price of enterprise-wide RAPS deployment, you could:
* Invest in more robust synthetic monitoring and canary deployments.
* Fund a dedicated app sec review cycle.
* Enhance your distributed tracing to actually see attack patterns in context.
I'd rather have a great WAF and spend the rest on observability. Has anyone actually measured the incremental blocked attacks that RASP caught that a WAF missed? Need real numbers, not sales slides.
/skeptical
Show me the methodology.
I'm a senior DevOps engineer at a 500-person SaaS company, running a K8s platform with over 200 microservices. We trialed Imperva RASP alongside Cloudflare WAF for six months.
* **Incremental Detection**: RASP caught ~12 legitimate attacks our WAF missed over the period, all were business-logic or auth-bypass attempts targeting a few specific Java apps. It flagged 1500+ false positives we had to tune.
* **Performance Overhead**: We saw consistent 8-12% increased CPU utilization on our app pods, and request latency spikes up to 30% for certain SQL-heavy endpoints under load.
* **Hidden Cost**: The real cost isn't just licensing. It's the engineering hours. We spent roughly 3 FTE-weeks per quarter on tuning, updating, and correlating its alerts with our APM and SIEM.
* **Clear Win**: RASP is defensible for a small set of crown-jewel, legacy apps with known vulns you can't patch. For modern, continuously deployed services, its value plummeted.
I'd take a well-tuned WAF and spend the savings on observability. If you have specific high-risk, unmaintained apps, then scope RASP to just those. For a clean call, tell us your app portfolio mix and your team's capacity for managing another security data source.
Agree on the core point. But your ROI alternative is still just monitoring and tracing.
The real missed opportunity is using your existing product analytics. You're already tracking user events. Enrich those with security flags from a WAF log feed. Build a cohort of "users who triggered a WAF rule" and measure their conversion/retention against baseline.
That's how you find the actual business logic attacks - not by adding more bloated instrumentation.
If it's not a retention curve, I don't care.