SAST checks the logic of code you wrote, secret scanning looks for credentials committed anywhere, and IaC scanning checks infrastructure files such as Terraform and Kubernetes YAML for risky settings. They read different inputs and find different problems, so one does not replace another.
Side by side
| SAST | Secret scanning | IaC scanning | |
|---|---|---|---|
| Reads | Application source | Files, history, issues, logs | Terraform, YAML, Dockerfiles |
| Finds | Injection, unsafe calls, weak crypto | API keys, passwords, tokens, private keys | Public storage, privileged pods, open ports |
| When | PR and nightly | Pre-commit, PR and history sweep | PR, before apply |
| Misses | Dependencies, config, secrets in other places | Logic flaws, misconfiguration | Application code, running state |
| Typical fix | Change code | Revoke and replace the credential | Change the configuration |
A simple example
A developer writes a handler that builds a SQL string from input, commits a cloud key in a test script, and adds a Kubernetes manifest with a privileged container. Three problems, three different scanners. Each of them is invisible to the other two.
Where dependency scanning fits
None of these three look at the packages you import. That is software composition analysis. A repository check normally combines all four. See how to scan a GitHub repository and SAST versus SCA.
How to sequence adoption
- Secret scanning first. It is the cheapest and the findings are the most urgent.
- Dependency scanning next, since most known CVEs are there.
- IaC scanning when infrastructure is code.
- SAST once the team can triage its output without burning out.
Order depends on your risk. A team that ships infrastructure daily may want IaC scanning earlier.
What none of them replace
Testing a running application is DAST. Human review and penetration testing find chained and business logic problems. A clean result from all of these is not proof of safety. See a clean scan does not mean your software is safe.
How Safeguard helps
Safeguard provides SBOM and dependency scanning with reachability analysis, and policies, gates and guardrails you can apply before merge. You can try the free scan on a repository.
Quick check
Can SAST find hardcoded secrets?
Sometimes, through rules for literal passwords. Dedicated secret scanning is broader, covering history and non code sources.
Does IaC scanning check the live cloud?
No. It checks files before deploy. Live state needs a separate check.
Last reviewed: 19 October 2026.
