How do you secure Infrastructure as Code in the pipeline?

Most cloud breaches trace back to misconfiguration, not exotic exploits. Since infrastructure is now defined as code, you can catch those misconfigurations the same way you catch bugs — by scanning the code.

What IaC scanning does

An IaC scanner statically analyzes infrastructure definitions — Terraform, CloudFormation, ARM/Bicep, Kubernetes manifests, Helm charts — against a library of security rules and your own policies. It flags the classics: storage buckets exposed to the public, security groups open to 0.0.0.0/0, unencrypted volumes, overly broad IAM roles, missing logging. Tools like Checkov, tfsec, and KICS plug straight into CI and run on every pull request.

Why scan the template, not the resource

This is the key insight. A single module might provision dozens of resources across many environments. Fix the template once and every future deployment is correct; remediate the live resource and it drifts back the next time someone runs the pipeline. Pre-apply scanning is also dramatically cheaper — you're editing a file, not racing to lock down a publicly exposed database that's already serving traffic.

Policy as code and exceptions

Mature teams express their guardrails as policy-as-code (e.g. OPA/Rego, or the scanner's own policy language) so rules are versioned and consistent. When a finding is a legitimate exception, you don't disable the scanner — you record a documented, time-boxed, reviewed suppression so the exception is auditable rather than silent.

Pair it with runtime checks

IaC scanning only sees what's in the templates. Combine it with Cloud Security Posture Management (CSPM) to catch drift and resources created outside the pipeline.

What interviewers look for

They want the "fix the template, not the resource" reasoning, awareness of real tools, and a sane approach to exceptions that keeps the gate meaningful.