Performing Container Security Scanning With Trivy

Performing Container Security Scanning with Trivy

Overview

Trivy is an open-source security scanner by Aqua Security that detects vulnerabilities in OS packages and language-specific dependencies, infrastructure-as-code misconfigurations, exposed secrets, and software license issues across container images, filesystems, Git repositories, and Kubernetes clusters. Trivy generates Software Bill of Materials (SBOM) in CycloneDX and SPDX formats for supply chain transparency. This skill covers comprehensive container image scanning, CI/CD pipeline integration, Kubernetes operator deployment, and scan result triage for security operations.

When to Use

Trigger phrases:

• "performing container security scanning with trivy"

• "Scan container images, filesystems, and Kubernetes manifests for vulnerabilities"

• When conducting security assessments that involve performing container security scanning with trivy

• When following incident response procedures for related security events

• When performing scheduled security testing or auditing activities

• When validating security controls through hands-on testing

Prerequisites

• Trivy v0.50+ installed (binary, Docker, or Homebrew)
• Docker daemon access for local image scanning
• Container registry credentials for remote image scanning
• CI/CD platform (GitHub Actions, GitLab CI, Jenkins) for pipeline integration
• Kubernetes cluster for Trivy Operator deployment (optional)

Steps

# Example: IOC detection
import re

IOC_PATTERNS = {
    "ip": r"\b(?:\d{1,3}\.){3}\d{1,3}\b",
    "domain": r"\b[a-z0-9-]+\.[a-z]{2,}\b",
    "hash_md5": r"\b[a-f0-9]{32}\b",
    "hash_sha256": r"\b[a-f0-9]{64}\b",
}

def extract_iocs(text: str) -> dict:
    return {k: re.findall(v, text) for k, v in IOC_PATTERNS.items()}

1. Prepare the environment — ensure write-blocker is connected and test workstation is ready
2. Document the source — record device serial, model, and pre-acquisition hash
3. Acquire the image — use the appropriate tool with hash verification enabled
4. Verify integrity — compare source and image hashes; document any discrepancies
5. Analyze and report — perform the analysis and document findings with chain of custody

Step 1: Scan Container Images

Run vulnerability and secret scanning against container images from local builds or remote registries. Configure severity thresholds and ignore unfixed vulnerabilities.

Step 2: Generate SBOM

Produce CycloneDX or SPDX SBOM documents from scanned images for supply chain compliance and vulnerability tracking across the software lifecycle.

Step 3: Scan IaC and Kubernetes Manifests

Detect misconfigurations in Dockerfiles, Kubernetes YAML, Terraform, and Helm charts using built-in policy checks aligned with CIS benchmarks.

Step 4: Integrate into CI/CD

Add Trivy scanning as a pipeline gate that blocks builds with critical/high vulnerabilities, generates SARIF reports for GitHub Advanced Security, and produces JUnit XML for test dashboards.

Expected Output

JSON/table report listing CVEs with severity, CVSS scores, fixed versions, affected packages, misconfiguration findings, and exposed secrets with file locations.

When NOT to Use

• You don't have explicit written authorization to test
• Task is about defense/detection, not offense (use detection skills)
• You need to implement security controls (use implementing-* skills)
• Task requires compliance auditing (use auditing-* skills)
• You're investigating an incident (use incident response skills)
• Target is out of scope for your engagement
• Task is about vulnerability scanning only (use scanning tools)

Red Flags

• Performing actions without explicit written authorization from the asset owner
• Testing against production systems without a defined scope and rules of engagement
• Failing to use write-blockers when acquiring forensic evidence
• Not verifying hash integrity before and after imaging
• Modifying original evidence during analysis

Process

1. Reconnaissance — Gather target information, identify attack surface, enumerate services
2. Analysis/Exploitation — Execute the technique, analyze results, document findings
3. Reporting — Document IOCs, write findings, provide remediation recommendations

Verification

• All steps executed successfully against a test environment before production use
• Output documented with screenshots or logs demonstrating expected behavior
• Hash values computed and verified match between source and image
• Chain of custody log complete with timestamps and examiner names
• Analysis tools and versions documented for reproducibility

Anti-Rationalization Table