Shift Left Security

TL;DR: Shift Left Security

Shift Left Security means starting security testing and enforcement as early as possible in the software development process. Instead of waiting until just before deployment, teams address security from the beginning.

This approach helps you:

• Catch vulnerabilities early when they are easiest and cheapest to fix.
• Empower developers to own security without slowing down their workflow. What if security checks felt as natural as unit tests? By framing security as a means of developer empowerment, we foster intrinsic motivation to integrate security seamlessly into everyday routines. This autonomy drives a proactive approach to security, enhancing both productivity and the overall security posture.
• Reduce the cost of rework by fixing issues during the coding phase instead of in production.

The goal of Shift Left Security is to make security a continuous part of the development process so that code is secure by design.

What Is Shift Left Security

Shift Left Security is a strategy for application security. It means testing for security issues and scanning for vulnerabilities while coding and building, not just during testing or deployment.

In a traditional “Waterfall” model, security checks happen at the end. This is often visualized as the “right” side of the timeline. Shifting left moves these checks to the “left” side. It integrates them into Integrated Development Environments (IDEs), Git repositories, and CI/CD pipelines.

In simple terms :

Shift Left Security means testing your code for security flaws while you write it, so you do not ship bugs to production.

Why Shift Left Security Matters

When you leave security for the final stage of development, you create a bottleneck. If a critical vulnerability is found days before launch, you either delay the release or ship with risk.

So why is Shift Left Security important?

Fixing bugs in production is costly. According to NIST, fixing a defect in production can cost 30 to 100 times more than fixing it during coding.

Velocity requires automation. Modern DevOps teams deploy multiple times a day. Manual penetration tests cannot keep up. Automated ‘left-shifted’ tools run with every commit. While automated scans surface issues efficiently, human review still provides essential context and judgment, ensuring a balanced approach.

Developers need quick feedback. It’s easier to fix a security issue while the code is still fresh in their mind, rather than weeks later after moving on to something else.

Security is a shared responsibility. It bridges the gap between security teams and engineering. This makes security an enabler rather than a gatekeeper.

How Shift Left Security Works

Shift Left Security catches vulnerabilities in code and dependencies before the application is built or deployed.

1. Detect Issues in the IDE (Pre-Commit)

Tools integrate directly into the developer’s coding environment (VS Code, IntelliJ) to flag issues in real-time.

• Static Application Security Testing (SAST): Scans source code for insecure coding patterns (e.g., SQL injection).
• Secret Detection: Warns if a developer attempts to paste an API key or token into the code.

Goal: Stop insecure code from ever entering the version control system.

2. Automate Scans in CI/CD (Pull Requests)

Security scans run automatically whenever code is pushed to the repository or a Pull Request is opened.

• Software Composition Analysis (SCA): Checks open-source libraries for known vulnerabilities (CVEs).
• Infrastructure as Code (IaC) Scanning: Checks Terraform or Kubernetes files for misconfigurations.

Goal: Catch issues during the peer review process before merging code.

3. Enforce Quality Gates

Pipelines are configured to fail the build if high-severity vulnerabilities are detected.

• Example: If a “Critical” vulnerability is found in a Docker image, the pipeline stops. The deployment is blocked until the issue is resolved.

Goal: Prevent vulnerable artifacts from reaching staging or production.

4. Continuous Feedback Loop

Results from scans are sent directly to the tools developers use, such as Jira, Slack, or GitHub Issues. This avoids the need for separate PDF reports.

Goal: Integrate security findings into the existing engineering workflow.

Common Risks Detected by Shift Left

Examples of issues Shift Left Security can detect early:

• Hardcoded Secrets: AWS keys, database passwords, or API tokens committed to Git. Catching these early not only prevents security breaches but also saves the time and resources required for costly credential rotations later.
• Vulnerable Dependencies: Using an old version of Log4j or OpenSSL with known exploits.
• Injection Flaws: SQL injection (SQLi) or Cross-Site Scripting (XSS) in source code.
• Insecure Infrastructure: S3 buckets with public access or containers running as root.
• Compliance Violations: Code that violates GDPR or PCI-DSS requirements.

Example in Practice

A developer is working on a new login feature for a Node.js application.

Without Shift Left: The developer finishes the code, merges it, and deploys it to staging. Two weeks later, the security team runs a scan and finds a hardcoded database password. A mix of frustration and panic sets in as the team scrambles to address the issue. The much-anticipated Friday launch slips away, turning into a Monday morning emergency meeting, where the release is put on hold. The developer is tasked with rewriting the authentication module while stakeholders fret over the unwelcome delay.

With Shift Left (using Plexicus):

1. The developer commits the code.
2. The CI/CD pipeline triggers a Plexicus scan.
3. The scan detects the hardcoded password immediately.
4. The build fails. The Pull Request is flagged with the specific line number.
5. The developer removes the password, uses an environment variable, and commits again.
6. The build passes.

Result: The vulnerability never left the development branch. The release schedule stayed on track.

Who Uses Shift Left Security

• Developers - to check their own code for errors before peer review.
• DevOps Engineers - to automate security gates in CI/CD pipelines.
• AppSec / DevSecOps Teams - to configure policies and monitor the overall security posture.
• Engineering Managers - to ensure technical debt and security risks are managed without slowing velocity.

When to Apply Shift Left Security

Shift Left Security should be applied throughout the early SDLC

• Local Development - pre-commit hooks and IDE plugins.
• Code Commit - automated scanning of branches and Pull Requests.
• Build Artifact - scanning container images and compiled binaries.
• Staging - dynamic analysis (DAST) on running applications before ship to production

Key Capabilities of Shift Left Tools

Most Shift Left security solutions provide:

• SAST (Static Application Security Testing): Analyzing source code.
• SCA (Software Composition Analysis): Checking open-source libraries.
• Secret Detection: Finding hardcoded credentials.
• IaC Security: Scanning infrastructure configurations.
• CI/CD Integration: Native plugins for GitHub, GitLab, Jenkins, etc.
• Developer-First Remediation: Showing exactly where the fix is needed (file and line number).

Example tools: specialized scanners or unified platforms like Plexicus ASPM, which combines code, secret, and container scanning into a single workflow.

Best Practices for Shift Left Security

• Start Small: Do not break the build for every minor issue. Start by blocking only “Critical” and “High” severity findings.
• Minimize False Positives: Tune your scanners to avoid alerting on irrelevant issues so developers do not ignore them.
• Fast Scans: Ensure security checks do not add significant time to the build process.
• Educate Developers: Use findings as a learning opportunity rather than a punishment.
• Scan Everything: Cover proprietary code, open-source dependencies, and infrastructure configurations.

Related Terms

• DevSecOps
• SAST (Static Application Security Testing)
• SCA (Software Composition Analysis)
• CI/CD Security