Security, correct header configuration, and robust HTTPS are foundational for user trust and search engine indexing. This technical audit checklist module focuses on server-level and application-level controls that influence site security, integrity, and SEO performance. The goal is to provide a repeatable set of checks that teams can run during audits and before public launches.
Cover TLS/HTTPS configuration, HTTP security headers, cookie scope and flags, content security policy (CSP), mixed content detection, and vendor integrations that handle user data. Prioritize checks that protect user data, prevent content injection, and avoid technical conditions that trigger deindexing or penalties.
Verify that TLS certificates are valid, chain correctly, and use modern ciphers. Check for HTTP to HTTPS redirection completeness and ensure HSTS is configured with an appropriate max-age and includeSubDomains where applicable. Validate that OCSP stapling is enabled and that protocol versions exclude legacy weak protocols.
Include checks for commonly recommended headers: Content-Security-Policy, X-Frame-Options or frame-ancestors directives, Referrer-Policy, X-Content-Type-Options, Strict-Transport-Security, and Permissions-Policy. The module should specify expected header values, discuss trade-offs for restrictive policies, and provide guidance for incremental rollout of CSP using report-only mode.
Audit cookie attributes: Secure, HttpOnly, SameSite, domain, and path. Ensure session cookies are Secure and HttpOnly to reduce risk of theft, and use SameSite to mitigate CSRF. Check cookie scoping to prevent leakage across subdomains and avoid embedding sensitive tokens in URLs or client-side storage without encryption.
Scan pages for mixed content where HTTP subresources are loaded into HTTPS pages. For critical libraries and third-party scripts, recommend Subresource Integrity (SRI) where appropriate and feasible. Provide remediation steps for replacing insecure resources or proxying them via a secure CDN when necessary.
Catalog third-party scripts and assess the data they access and collect. Include checks for iframe sandboxing, limiting permissions, and verifying vendor privacy policies and data handling practices. For payment providers and any vendor handling PII, ensure compliance with industry standards and validate secure integration patterns.
Automate TLS scans, header presence checks, and mixed content detection. Manual review remains important for CSP iteration, third-party permissions, and evaluating business risk from vendor scripts. Capture outputs from scanners, sample header dumps, and screenshots of any resource loading errors as evidence for remediation tickets.
Include checks for monitoring and alerting: certificate expiry monitoring, SSL scanning alerts, and logging for unusual authentication attempts or traffic spikes. Validate that security-related logs are retained and accessible for incident response, and that contacts and runbooks exist for certificate replacement and header policy changes.
Define clear pass/fail criteria. For example, TLS valid and modern ciphers required for pass; missing HSTS could be medium severity; CSP missing for sites with high exposure could be high severity. For third-party scripts with access to user data, require a documented vendor assessment before allowing production deployment.
Make security checks gate criteria for public releases. Use staged feature flags and report-only modes for CSP and other restrictive headers to observe impact before enforcement. Maintain an allowlist for essential third-party vendors and require security sign-off for any additions that access user data.
Beware of overbroad CSP rules that break functionality, and of hasty HSTS settings that can lock sites if misconfigured. Avoid embedding tokens in front-end code and rely on secure server-side handling for authentication where possible. Ensure developers have accessible guidance and remediation recipes for common header and cookie issues.
A focused security and headers module helps teams mitigate common vulnerabilities and protect both users and search presence. Regular automated scans, paired with manual policy reviews and a clear remediation workflow, make security checks operational and effective for fast-moving sites.