Subresource Integrity (SRI) Checks

What is Subresource Integrity (SRI) Checks?

Counts external scripts and stylesheets lacking integrity= attributes. Without SRI hashes, a compromised CDN can silently serve malicious code to all users.

This vulnerability class falls under the Configuration & Deployment Management phase of the OWASP Testing Guide (WSTG-CLNT). Security engineers prioritise configuration & deployment management checks early in an assessment because weaknesses here provide a foothold that amplifies the severity of vulnerabilities found in later phases.

Security Impact

SRI ensures the browser refuses to execute any resource whose content has been tampered with, eliminating CDN supply-chain risk at zero infrastructure cost.

Left undetected, subresource integrity (sri) checks issues can persist unnoticed for months. Continuous automated scanning ensures your team receives an alert the moment a regression or new exposure is introduced — long before an attacker discovers it through manual enumeration or automated offensive tooling.

How DygDog Detects It

DygDog evaluates client-side security posture by examining Content Security Policies, DOM storage patterns, JavaScript library versions, and inter-origin communication channels.

The Subresource Integrity (SRI) Checks check is implemented as a passive scan module, meaning it never sends dangerous payloads or modifies application state. Scans complete in approximately 600 ms and run continuously in the background so your security posture reflects the current state of your site — not a point-in-time snapshot.

Remediation Approach

Deploy a restrictive Content Security Policy that eliminates unsafe-inline and unsafe-eval; keep third-party JavaScript dependencies updated and integrity-checked via SRI; and audit postMessage handlers for missing origin verification.

DygDog does not stop at detection. When a Subresource Integrity (SRI) Checks finding is confirmed, the platform generates infrastructure-aware, copy-paste-ready remediation snippets using frontier AI models. Instead of generic advice you need to adapt, you receive code that targets your exact server, framework, and configuration.

OWASP References

This check maps to the following OWASP Testing Guide test cases:

• WSTG-CLNT-13View OWASP WSTG →

Related Configuration & Deployment Management Checks

These checks belong to the same testing phase and are often assessed together:

• TLS/SSL Configuration

  Validates HTTPS enforcement, certificate validity, protocol versions, and cipher suite strength.

• HTTP Methods Testing

  Tests for dangerous HTTP methods (TRACE, PUT, DELETE, OPTIONS) that may be unintentionally enabled.

• Security Headers Analysis

  Comprehensive check for HSTS, CSP, X-Frame-Options, X-Content-Type-Options, Referrer-Policy, and Permissions-Policy.

• File Extension & MIME Handling

  Tests how the server handles various file extensions and MIME types, looking for bypass opportunities.