SAST vs DAST: Static vs Dynamic Application Security Testing

Mon, 03 Aug 2026 04:19:31 +0900

Overview

SAST scans an application’s source code at rest to catch insecure patterns before the app ever runs, while DAST attacks a running application from the outside to find exploitable flaws in its live behavior. Teams use both because each catches vulnerability classes the other structurally cannot see.

Comparison Diagram

Comparison Table

Aspect	SAST	DAST
What it examines	Source code, bytecode, or binaries at rest	A running, deployed application from outside
Access level	White-box — full visibility into code internals	Black-box — only sees inputs and outputs like an attacker
When in SDLC	Early, during coding and in CI on every commit	Later, once a build is deployed to a test or staging environment
Environment needed	None — analyzes files directly, no app needs to run	A live, reachable instance of the application
Vulnerability classes found	Insecure code patterns: SQL string building, hardcoded secrets, unsafe deserialization	Exploitable runtime behavior: auth bypass, injection responses, misconfigured headers
Language/stack dependency	Tied to the language and framework being parsed	Language-agnostic — probes over HTTP/HTTPS regardless of stack
False positive tendency	Higher — flags patterns that may not be reachable or exploitable	Lower — findings are confirmed by actual exploit attempts
Remediation output	Exact file and line number to fix	Vulnerable URL, parameter, and request/response evidence

Key Differences

SAST inspects source code without running it; DAST attacks a live instance without seeing its internals
SAST fits early into CI pipelines per-commit; DAST needs a deployed build to test against
SAST pinpoints the exact line number; DAST reports the vulnerable endpoint and payload
SAST is prone to false positives from unreachable code paths; DAST confirms via actual exploitation
SAST misses runtime configuration flaws that DAST catches, like missing security headers or session issues

When to Use Each

SAST

Sast on IT Comparison

SAST vs DAST: Static vs Dynamic Application Security Testing

Overview

Comparison Diagram

Comparison Table

Key Differences

When to Use Each