# BeaverCheck Audit Report — https://ndl.go.jp **Date:** April 22, 2026 **URL:** https://ndl.go.jp **Overall Grade:** C (70/100) **Report:** https://beavercheck.com/results/d8542a4a-7fa8-4d2e-8785-230c29e6f404 ## Top Findings 1. **[CRITICAL]** Content-Security-Policy header is missing — Security > Security Headers 2. **[CRITICAL]** HSTS header is missing — Security > Security Headers 3. **[CRITICAL]** No Content-Security-Policy header found — Security > Content Security Policy 4. **[CRITICAL]** 4 button(s) with no accessible text — Accessibility > Link & Button Quality 5. **[WARNING]** 34 third-party resources (100% of weight) — Performance > Page Weight Inventory --- ## Lighthouse Scores | Category | Score | |----------|-------| | Performance | 31 | | Accessibility | 85 | | Best Practices | 100 | | SEO | 100 | --- ## Security ### Security Headers (F — 5/100) *1 of 10 headers properly configured* - **[CRITICAL]** HSTS header is missing — Strict-Transport-Security forces browsers to use HTTPS, preventing downgrade attacks. Add the header with a max-age of at least 1 year. - **[WARNING]** X-Content-Type-Options header is missing — This header prevents MIME-type sniffing, which can lead to XSS attacks. Set it to 'nosniff'. - **[WARNING]** X-Frame-Options header is missing — This header prevents clickjacking by controlling who can embed your page in a frame. Set it to DENY or SAMEORIGIN. - **[WARNING]** Referrer-Policy header is missing — Controls how much referrer information is sent with requests. Set to 'strict-origin-when-cross-origin' or stricter. - **[WARNING]** Permissions-Policy header is missing — Controls which browser features (camera, microphone, geolocation) are allowed. Set it to restrict unused features. - **[CRITICAL]** Content-Security-Policy header is missing — CSP is the most important header for preventing XSS attacks. See the CSP section for detailed analysis. - **[WARNING]** Cross-Origin-Opener-Policy header is missing — COOP isolates your browsing context, preventing cross-origin side-channel attacks. Set to 'same-origin'. - **[WARNING]** Cross-Origin-Embedder-Policy header is missing — COEP prevents loading cross-origin resources without explicit permission. Required for SharedArrayBuffer and high-resolution timers. - **[PASS]** X-Powered-By header is not present - **[WARNING]** Server header reveals version information — The Server header discloses the software version, aiding attackers in targeting known vulnerabilities. Remove the version number. ### Content Security Policy (F — 0/100) *No enforcing CSP policy found* - **[CRITICAL]** No Content-Security-Policy header found — CSP is the most effective defense against XSS attacks. Add a Content-Security-Policy header to restrict resource loading. ### TLS & Certificates (A+ — 100/100) *TLS 1.3, 7 checks passed* - **[PASS]** TLS 1.3 is used - **[PASS]** Strong cipher suite is used - **[INFO]** HTTP/2 is not negotiated — HTTP/2 provides multiplexing and header compression for better performance. - **[PASS]** Certificate is valid (expires in 263 days) - **[PASS]** Certificate chain has 3 certificates - **[PASS]** Certificate uses modern signature algorithm - **[PASS]** Certificate covers 1 domain(s) - **[PASS]** Certificate is issued by a trusted CA ### Cookie Security (A+ — 100/100) *No cookies set — no cookie security risks* - **[PASS]** No cookies set — no cookie security risks --- ## Advanced Security ### Subresource Integrity (F — 20/100) *0 of 1 external resources have SRI* - **[WARNING]** External link from www.ndl.go.jp lacks integrity attribute — Without SRI, if this CDN is compromised, attackers could inject malicious code. ### JS Library Vulnerabilities (A+ — 100/100) *No known vulnerabilities* - **[PASS]** No known JavaScript library vulnerabilities detected ### Information Leakage (A+ — 100/100) *No exposures* - **[INFO]** No security.txt found — Consider adding a security.txt at /.well-known/security.txt. - **[PASS]** No sensitive files exposed ### Email Security (D — 50/100) *DMARC: none* - **[WARNING]** DMARC policy is none — monitoring only — This only monitors, it doesn't block spoofed emails. Change to p=quarantine or p=reject. ### Permissions-Policy (D — 40/100) *No header set* - **[WARNING]** No Permissions-Policy header — Consider adding a Permissions-Policy header to restrict browser feature access from embedded content. ### CORS Configuration (B — 80/100) *No CORS headers* - **[PASS]** No CORS headers present — secure default --- ## Performance ### Page Weight Budget (F — 12/100) *3.5 MB transferred, 35 requests* - **[WARNING]** Page weighs 5.9 MB (3.5 MB transferred) - **[WARNING]** Images are 1.4 MB — compress or use modern formats — Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size. - **[WARNING]** JavaScript is 1.1 MB — consider code splitting or lazy loading — Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts. - **[INFO]** Fonts are 898 KB — consider subsetting or using system fonts — Subset fonts to include only used characters, or switch to system font stacks. - **[PASS]** 35 HTTP requests - **[INFO]** Estimated 0.73 g CO2 per page load ### Third-Party Impact (D — 50/100) *100% third-party, 0 ms blocking* - **[WARNING]** Third-party code accounts for 100% of page weight (3.5 MiB of 3.5 MiB) - **[PASS]** Third-party blocking time is low (0 ms) ### Text Compression (A+ — 100/100) *All text resources are compressed* - **[PASS]** All text resources are compressed ### Image Optimization (B — 70/100) *9 images, 0 KB saveable* - **[WARNING]** https://www.ndl.go.jp/file/part/top/pickups/main_j... is missing width/height — may cause layout shift — Set explicit width and height to prevent CLS. - **[WARNING]** https://www.ndl.go.jp/assets/images/naiic.png is missing width/height — may cause layout shift — Set explicit width and height to prevent CLS. - **[WARNING]** https://www.ndl.go.jp/assets/images/brand/x.png is missing width/height — may cause layout shift — Set explicit width and height to prevent CLS. - **[WARNING]** https://www.ndl.go.jp/assets/images/brand/youtube.... is missing width/height — may cause layout shift — Set explicit width and height to prevent CLS. ### JS Execution Cost (D — 40/100) *2437ms total JS execution* - **[WARNING]** Unattributable: 963ms CPU time - **[WARNING]** https://www.ndl.go.jp/_nuxt/xQirD6gr.js: 898ms CPU time - **[WARNING]** https://www.ndl.go.jp/: 576ms CPU time - **[WARNING]** Third-party scripts: 2437ms (100% of total) ### Font Loading (A+ — 100/100) *3 fonts (898 KB)* - **[INFO]** 3 font(s) use font-display: swap (FOUT risk but functional) ### JS Bundles (D — 40/100) *7 scripts, 465 KB unused* - **[WARNING]** https://www.ndl.go.jp/_nuxt/xQirD6gr.js: 465 KB unused (43%) — Consider code splitting or tree shaking to reduce unused code. - **[INFO]** Total unused JavaScript: 465 KB ### Resource Caching (A+ — 100/100) *All resources properly cached* - **[PASS]** No caching issues found ### Critical Rendering Path (A+ — 100/100) *No render-blocking resources* - **[PASS]** No render-blocking resources detected ### Resource Hints (A+ — 100/100) *7 hints, 0 missing preconnects* - **[PASS]** Page uses 7 resource hint(s) ### Page Weight Inventory (F — 35/100) *35 resources · 3.5 MB · 465 KB savings available* - **[WARNING]** Page weight 2.5 MB over 1MB target - **[INFO]** ~465 KB of savings available - **[WARNING]** 34 third-party resources (100% of weight) - **[INFO]** 6 resources over 200KB ### Render-Blocking Resources (A+ — 100/100) *No render-blocking resources detected* - **[PASS]** No render-blocking resources detected in ### Third-Party Resources (A+ — 100/100) *No third-party resources detected* --- ## Content Quality ### Links (A+ — 100/100) *89 links checked, 89 healthy, 0 broken* - **[PASS]** 89 of 89 links are healthy ### Mixed Content (A+ — 100/100) *No mixed content detected — all resources use HTTPS.* - **[PASS]** No mixed content detected — all resources use HTTPS ### Open Graph (A — 95/100) *Open Graph tags are well configured for social sharing.* - **[INFO]** og:title is short (7 characters) — Ideal length is 25–60 characters for social sharing previews. - **[INFO]** Missing twitter:card — Without twitter:card, Twitter falls back to Open Graph tags. Adding it gives you more control. ### Structured Data (C — 75/100) *1 JSON-LD block(s) found — some improvements recommended.* - **[CRITICAL]** Malformed JSON-LD block #1 — JSON parse error: Mismatch type map[string]interface {} with value array "at index 0: mismatched type with value\n\n\t[{\"@context\":\"https://schema.org\n\t^...............................\n" --- ## Infrastructure ### DNS Records (A — 90/100) *2 A records, 278 ms lookup* - **[PASS]** Resolves to 2 IPv4 address(es) - **[INFO]** No IPv6 (AAAA) records - **[PASS]** 5 nameserver(s) configured - **[PASS]** 2 mail exchanger(s) configured - **[INFO]** CAA records not checked — CAA record lookup requires a specialized DNS resolver. This check will be available in a future update. - **[PASS]** SPF record present in TXT - **[WARNING]** DNS resolution is slow (278 ms) — Slow DNS adds latency to every page load. Consider a faster DNS provider. ### Redirect Chain (B — 70/100) *1 redirect(s), 1889 ms total* - **[PASS]** Single redirect - **[INFO]** WWW normalization redirect - **[WARNING]** Redirect overhead: 1889 ms total ### IPv6 Readiness (C — 60/100) *No IPv6 support* - **[INFO]** No IPv6 (AAAA) records found — IPv6 support is increasingly important for global accessibility. About 40% of internet users have IPv6 connectivity. ### Crawlability (A+ — 100/100) *robots.txt present, sitemap with 1 URLs* - **[PASS]** robots.txt is present - **[PASS]** sitemap.xml is present - **[PASS]** sitemap.xml is valid XML - **[PASS]** sitemap.xml contains 1 entries - **[PASS]** Sitemap index with 1 child sitemaps - **[PASS]** robots.txt references sitemap ### URL Variants (B — 75/100) *www/non-www, trailing slash, HTTP→HTTPS* - **[CRITICAL]** Both www and non-www versions serve content - **[PASS]** HTTP correctly 301-redirects to HTTPS ### Domain Intelligence *Domain intelligence data not available* --- ## Compliance ### WCAG Compliance (A+ — 100/100) *No testable criteria* ### Cookie Consent & Privacy (B — 80/100) *No consent signals detected* - **[WARNING]** No privacy policy link detected — A privacy policy page is recommended for transparency and may be legally required. - **[INFO]** No terms of service link detected - **[INFO]** No cookie consent banner detected - **[INFO]** This is an automated check, not legal advice — BeaverCheck detects technical indicators of consent management. This does not constitute a legal compliance assessment. Consult a privacy professional for GDPR/CCPA compliance. ### Language & i18n (A — 90/100) *Lang attribute present* - **[PASS]** attribute is present - **[PASS]** value is valid - **[INFO]** No Content-Language HTTP header - **[INFO]** Language signals are inconsistent — The attribute and Content-Language header should agree. ### Readability & Typography (A+ — 100/100) *Font sizes and tap targets checked* ### Viewport Configuration (B — 80/100) *Viewport properly configured* - **[PASS]** Viewport meta tag is present - **[WARNING]** width=device-width is not set - **[PASS]** User zooming is allowed ### Third-Party Trackers (A+ — 100/100) *No third-party trackers detected* - **[PASS]** No third-party trackers detected --- ## Legal ### Legal Page Ecosystem (F — 15/100) *1 of 7 expected legal pages detected* - **[WARNING]** Privacy Policy not detected — No link matching common Privacy Policy URL patterns or link text was found. Most websites are expected to have a Privacy Policy, especially those collecting user data. - **[WARNING]** Terms of Service not detected — No link matching common Terms of Service URL patterns or link text was found. Most websites are expected to have a Terms of Service, especially those collecting user data. - **[INFO]** Cookie Policy not detected — No link matching common Cookie Policy URL patterns or link text was found. Most websites are expected to have a Cookie Policy, especially those collecting user data. - **[PASS]** Accessibility Statement detected — Found at /accessibility, linked from footer. - **[INFO]** DMCA / Copyright Notice not detected — No link matching common DMCA / Copyright Notice URL patterns or link text was found. Most websites are expected to have a DMCA / Copyright Notice, especially those collecting user data. - **[INFO]** Refund / Returns Policy not detected — No link matching common Refund / Returns Policy URL patterns or link text was found. Most websites are expected to have a Refund / Returns Policy, especially those collecting user data. - **[INFO]** Acceptable Use Policy not detected — No link matching common Acceptable Use Policy URL patterns or link text was found. Most websites are expected to have a Acceptable Use Policy, especially those collecting user data. ### Copyright Notice (C — 55/100) *No copyright notice detected* - **[INFO]** No copyright notice detected — No copyright notice detected in the page content. While not legally required in most jurisdictions (copyright exists automatically), a notice is standard practice and signals site ownership. ### Regulatory Indicators *2 regulatory indicator(s) detected* - **[INFO]** This is a technical scan, not a legal assessment — BeaverCheck detects technical indicators that may suggest regulatory relevance. This is not a compliance audit and should not be relied upon for legal decisions. Consult qualified legal counsel for compliance assessments. - **[INFO]** GDPR indicators detected (moderate confidence) — Indicators suggesting GDPR may be relevant: Privacy policy page found. EU General Data Protection Regulation — governs collection and processing of personal data of EU residents. - **[INFO]** ADA indicators detected (moderate confidence) — Indicators suggesting ADA may be relevant: Accessibility statement page found. Americans with Disabilities Act / Section 508 — requires digital accessibility for people with disabilities. ### Third-Party Data Sharing *0 third-party service(s) detected* - **[INFO]** Data inventory for transparency purposes — This inventory identifies third-party services that receive data from your site visitors. Under regulations like GDPR (Article 30), maintaining records of data processing activities is commonly considered a best practice. This automated scan provides a starting point — it may not capture all data flows. - **[INFO]** No recognized third-party data-sharing services detected — This page does not appear to load external tracking, analytics, or advertising scripts. ### Compliance Badges (C — 55/100) *0 compliance badge(s) detected* - **[INFO]** No compliance badges detected — No recognized compliance certification badges or seals were found. This is common — many sites do not display compliance badges. --- ## Availability ### CDN & Delivery (D — 50/100) *No CDN detected* - **[WARNING]** No CDN detected — A CDN can significantly improve load times for users around the world by caching content at edge nodes closer to them. ### HTTP Caching (F — 30/100) *No cache headers* - **[WARNING]** No Cache-Control header found — Browsers will use heuristic caching, which can be unpredictable. Set explicit cache headers. ### Transport Security (B — 75/100) *HTTP/3, HSTS, and TLS version analysis* - **[INFO]** HTTP/3 (QUIC) not advertised — HTTP/3 eliminates head-of-line blocking. If your CDN supports it, consider enabling it. - **[WARNING]** Missing Strict-Transport-Security header — HSTS tells browsers to only use HTTPS, preventing SSL stripping attacks. - **[PASS]** TLS 1.3 in use (fastest handshake, 1-RTT) --- ## Accessibility ### Landmark Structure (A — 85/100) *5 landmarks* - **[PASS]**
landmark present - **[PASS]** 2