Is Your API a Sitting Duck? Why You Need a Security Score for Every API

Have you ever wondered:

• How secure are your internal and external APIs—really?
• Could a forgotten, low-traffic API be the weakest link in your security chain?
• What if you had a “credit score” for every API to tell you exactly which ones are high risk?

Welcome to the world of API Security Scoring—a game-changer for organizations serious about reducing their attack surface, boosting DevSecOps accountability, and staying compliant in a threat-heavy, regulation-filled world.

In this post, I’ll answer the burning questions many teams are asking today:

• What is an API security score?
• Why do I need it if I already do API testing or vulnerability scans?
• Are there tools that calculate these scores, or do I need to build it myself?
• How are real companies using API security scores to improve their defenses?

Let’s dive in.

Why Should APIs Have a Security Score?

APIs are the digital glue of every modern app—connecting services, exposing data, and enabling automation. But they’re also prime targets for attackers. In fact, APIs have become the #1 attack vector for many organizations, especially those with customer-facing platforms.

The problem? Most organizations don’t know which of their APIs are high-risk until it’s too late. That’s where API security scoring comes in.

Think of it like a credit score for your API’s security posture. It’s a metric—usually on a 0–100 or risk-tiered scale—that tells you how risky an API is based on things like:

• Whether it uses strong authentication
• If it handles sensitive data (like PII or payment info)
• If it’s internet-facing or internal
• Whether it has known vulnerabilities or misconfigurations

With a good scoring system, you can prioritize fixes, flag shadow APIs, and make smart, risk-based decisions.

Why Traditional API Security Isn’t Enough

Most companies already run vulnerability scans or set up API gateways. So why add a security scoring layer?

Because traditional tools often:

• Focus only on individual issues (e.g., a missing auth header), not overall risk
• Don’t account for real-time API behavior or sensitivity
• Provide no clear way to compare APIs or track risk trends

API security scoring systems fill that gap by combining multiple risk signals into a single score. This makes it easier to answer high-level questions like:

• “Which APIs are the most dangerous right now?”
• “Have our API risks increased over the last quarter?”
• “Should we block a deployment because the new API is too risky?”

It’s a move from reactive defense to proactive, continuous risk management.

What Are the Benefits of API Security Scoring?

Adopting an API Security Scoring System yields numerous benefits for both technical teams and business stakeholders:

1. Support for Secure API Lifecycle Management: A scoring system isn’t just a one-time assessment; it supports security throughout the API lifecycle. During development, teams can use scores from design and testing tools to improve APIs before deployment. Once in production, continuous scoring (via automated scans or monitoring) ensures any drift or newly discovered issues are caught. This full-lifecycle approach embeds security into every phase – from planning and building to ongoing monitoring – and is essential for DevSecOps practices. It shifts security “left” (into development) and also “right” (into runtime governance), creating feedback loops that improve new API designs based on past scoring data.
2. Visibility into API Security Posture: A unified scoring dashboard offers at-a-glance visibility of every API’s security status. Teams can instantly identify the most vulnerable APIs (e.g. those handling sensitive data over insecure channels or with known weaknesses). This combats “shadow APIs” and blind spots by ensuring every API, internal or external, is accounted for and evaluated. According to industry reports, maintaining an accurate API inventory remains challenging, with only 15% of organizations confident in their API inventory. A scoring system that continuously discovers and scores APIs addresses this gap by illuminating all APIs and their risk levels in one place.
3. Risk-Based Prioritization of Remediation: Not all vulnerabilities carry equal weight – a minor misconfiguration on a low-sensitivity internal API is far less urgent than an authentication flaw on a public customer-facing API. Security scoring quantifies these differences, allowing teams to prioritize remediation efforts on high-risk APIs first.
4. Accountability Across Teams: By providing a clear metric, API scores create accountability for development and DevOps teams. Teams responsible for an API can track its score over time and strive to improve it by addressing security findings. Many organizations incorporate such metrics into their KPIs or compliance scorecards. For instance, a development team might have an objective to raise all critical APIs’ security scores above 90/100 by next quarter. This fosters a culture of security ownership. It also facilitates cross-team communication: management can use scores to ask informed questions (“Why is API X scoring low and what’s the remediation plan?”) and recognize teams that maintain high security standards.
5. Reduced Risk of Breaches and Incidents: Ultimately, the benefit of a security scoring system is a lowered risk of API breaches. By continuously monitoring and improving API scores, organizations plug security gaps before attackers exploit them. This is crucial as APIs are now the #1 attack vector for many breaches. In fact, security research finds that 98% of API attack attempts target external-facing APIs – precisely the kind of high-risk endpoints a scoring system would flag. With higher awareness and proactive fixes driven by scores, the likelihood and impact of successful attacks are minimized. Over time, organizations can correlate improvements in API scores with a reduction in security incidents, demonstrating a tangible ROI: fewer data breaches, avoidance of incident response costs, and protection of brand trust.

Existing API Security Scoring Frameworks and Tools

Several frameworks and tools exist that provide guidance or functionality for scoring API security. These range from industry-standard risk models to purpose-built API security platforms. Table 1 summarizes key frameworks and Table 2 highlights leading tools and their capabilities.

Table 1. API Security Scoring Frameworks and Standards

Framework/Standard	Scoring Approach and Focus	Key Elements
OWASP Risk Rating	Qualitative risk scoring based on Likelihoodand Impact. Often used to rank OWASP API Top 10 risks.	Likelihood = ease of exploit; Impact = technical & business damage. Provides High/Med/Low ratings (can be mapped to numeric scores). Useful for initial risk assessment of API vulnerabilities.
NIST Cybersecurity Framework (CSF)	Provides a high-level framework (Identify, Protect, Detect, Respond, Recover) for managing cybersecurity risk. Not a scoring system per se, but guides what to measure.	Encourages identifying all APIs and assessing their risk (aligns with Identify/Protect). New CSF 2.0 guidance explicitly highlights securing APIs as part of risk management. Can incorporate API risk scoring into an organization’s CSF implementation for continuous monitoring (Detect).
Common Vulnerability Scoring System (CVSS)	Standard for scoring individual vulnerabilities (0.0 to 10.0 scale) based on severity. Often applied to API vulnerabilities discovered through testing.	Considers exploitability (attack vector, complexity) and impact (confidentiality, integrity, availability) of a vulnerability. Many API scanning tools map findings to CVSS scores, enabling consistency with enterprise vulnerability management.
API Security Guidelines (e.g., NIST SP 800-204)	NIST SP 800-204 and related guidelines focus on microservices and API security strategies. They provide best practices which can be translated into scoring criteria (for example, whether an API enforces proper authentication, rate limiting, etc.).	Though not a direct scoring system, these guidelines suggest controls that a scoring system should check (like OAuth use, input validation, schema compliance). Organizations often create a checklist from such standards and score APIs on compliance percentage.

Sources: OWASP API Security Top 10 (2023), NIST CSF 2.0 updates for APIs

Table 2. API Security Scoring Tools and Platforms

Tool / Platform	Scoring Mechanism & Capabilities	Notable Features
APIsec(APIsec AI)	Automated API testing platform that conducts security scans (fuzzing, auth checks, OWASP Top 10 tests). While it identifies vulnerabilities, it also can assign a health score or risk level to an API based on test results (pass/fail of various categories).	Continuous Testing: Integrates into CI pipelines to test APIs pre-production.  Coverage: Extensive library of security test categories (over 100, covering OWASP and other API vuln types).  Output: Generates reports and potentially an aggregate risk score or grade for each API (e.g., percentage compliance or a grade A-F).
Traceable AI	Provides an automatic risk score for each API endpoint, updated continuously. Combines runtime data (traffic patterns, sensitive data flow, user behavior) with known vulnerabilities to score the likelihood and impact of a cyberattack on that API.	API Discovery: Auto-discovers internal, external, third-party APIs (eliminating blind spots).  Risk Analytics: Shows why an API is high-risk (e.g., handles PII data, exposed to public, high traffic volume).  Actionable Intelligence: Ranks “most risky APIs” to focus mitigation; offers free risk assessment for initial analysis.
Noname Security (Akamai API Sec)	Introduced customizable API risk scoring that aggregates multiple factors. Parameters include data sensitivity, number of requests, authentication quality, whether the API is internal vs. internet-facing, etc. Each API endpoint receives a score indicating its risk level.	Customization: Security teams can adjust weighting of risk factors to align with their priorities (e.g., give extra weight to data sensitivity).  API Lifecycle Coverage: Discovers APIs across environments, tests them (active testing against specs), and monitors traffic in runtime.  Dashboard: Central view with risk scores and trends; can trigger alerts when an API’s score worsens.
Salt Security	Focuses on API endpoint scoring as part of its posture management. Scores are derived from the types of sensitive data an API handles (PII, PCI, etc.), the history of attack attempts on it, and any security posture gaps (e.g., missing auth, misconfigurations).	Threat Correlation: Monitors attackers’ activities to see which APIs they target, turning attacker behavior into insights.  Posture Policies: Allows setting policies (rules) that, when violated by an API, lower its score (for example, an API without encryption or with excessive data exposure).  Integration: Can send alerts and findings to SIEMs, Jira, or CI/CD, enabling quick developer remediation.
42Crunch(API Security Audit)	Offers an API contract security audit tool that scores API definitions (OpenAPI/Swagger) on a 0-100 scale for security compliance. It checks for issues like weak authentication schemes, lack of encryption, and deprecated parameters, then assigns a score.	Design-Time Focus: Helps developers “shift left” by scoring the API design before implementation.  Detailed Guidelines: Each issue found is mapped to best practices (OWASP, NIST guidelines) and reduces the score.  CI/CD Integration: The audit can run in CI pipelines (e.g., via a Docker image) to fail builds if the score is below a set threshold, ensuring only secure API specs move forward.
Cequence(API Sentinel)	Provides API Security Posture Management with risk scoring for API endpoints. It continuously analyzes API traffic and configurations for risks, generating a score per API based on a customizable risk formula (similar to others, factoring data exposure, auth strength, anomalies).	API Shadow Detection: Finds unmanaged APIs and includes them in the scoring.  Custom Risk Factors: Users can define which factors (e.g. no schema, excessive parameters, unusual traffic) contribute more to risk.  Remediation Guidance: Ties each risk factor to recommended fixes (e.g., “enable rate limiting to improve score”).

Real-World Example: What Happens When You Don’t Score

Here’s a true story (names anonymized):

A fintech company had hundreds of microservices—but no visibility into API security. One day, attackers discovered a legacy API that still accepted traffic and didn’t require proper authentication. The result? A costly breach and reputational damage.

After the incident, the company implemented API security scoring with Traceable. Within weeks, they:

• Discovered 200+ undocumented APIs
• Flagged 20 critical APIs with scores below 50
• Raised scores across their stack by fixing misconfigs and removing old endpoints

Now, new APIs can’t go live unless their score hits 85+. They haven’t had a major incident since.

Getting Started: How to Bring API Scoring Into Your Org

Want to score your APIs? Here’s a quick roadmap:

1. Inventory Your APIs
   Use your API gateway or a discovery tool to find what you have.
2. Choose a Scoring Framework or Tool
   Start simple. Even a static score based on OWASP checks is a good step.
3. Integrate Into CI/CD
   Automate score checks in your dev pipeline. Block or warn on low scores.
4. Set Thresholds and Policies
   For example: “No internet-facing API below score 70 goes to prod.”
5. Make It Visual
   Dashboards = awareness. Show API scores alongside app health metrics.
6. Monitor, Improve, Repeat
   Track score changes over time and celebrate when teams raise them.

Final Thoughts

API security is no longer optional—and security scoring makes it manageable. With a scoring system in place, you don’t have to wonder if your APIs are secure. You’ll know. So ask yourself: What’s your API’s score? If you don’t know, it might be time to find out.