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Security report for highlightjs.org

Contact Privacy Inc. Customer 0164357247 · Technology · Canada

Medium risk. 9 critical or high findings in Email security, Security headers and 2 other checks.

Security score

60/100

Risk levelMedium

0–100, higher is better. How it is calculated

Highlight.js is a well-established open source project founded in 2012, providing a popular JavaScript syntax highlighting library supporting 192 languages and 512 themes. The website targets developers and technical users, offering comprehensive usage instructions and trusted by major platforms such as Stack Overflow and Discord. The business model centers on open source software distribution with community contributions and GitHub presence. Technically, the site uses modern web technologies including Next.js, Node.js, and Deno, hosted on Netlify, delivering fast and mobile-optimized performance with good SEO and accessibility features. Security posture is solid with HTTPS enforced and domain transfer protections, though explicit security headers and formal privacy/cookie policies are absent. The presence of a dedicated security contact email indicates some incident response readiness. Overall, the site is professional, trustworthy, and technically mature but could improve privacy compliance and security best practices.

Scanned

NIS2 and GDPR posture

GDPR outside view
35/ 100 · High
Checks completed
7of 7

NIS2 Art. 21(2)

  1. (a) Risk analysis and security policies: Not visible from outside
  2. (b) Incident handling: One indicator
  3. (c) Business continuity, backups and crisis management: Not visible from outside
  4. (d) Supply chain security: Not visible from outside
  5. (e) Secure acquisition, development and maintenance, including vulnerability handling: Partly checked
  6. (f) Assessing the effectiveness of security measures: Not visible from outside
  7. (g) Cyber hygiene and security training: Not visible from outside
  8. (h) Cryptography and encryption: Partly checked
  9. (i) HR security, access control and asset management: One indicator
  10. (j) Multi-factor authentication and secured communications: Not visible from outside

This scan rated NIS2 with an earlier keyword method that is no longer shown; rescan for the per-article view. Risk management, continuity, supply chain, training, MFA, management oversight (Art. 20) and incident reporting (Art. 23) need internal evidence, and Guard cannot tell whether NIS2 applies to this organisation.

GDPR is indicative only, based on publicly visible signals: Articles 7, 12, 13 and 32 of Regulation (EU) 2016/679 and Article 5(3) of the ePrivacy Directive. Not a certification or legal assessment.

Priority findings

9 findings rated critical or high. Fix these first.

  1. Email security

    SPF, DKIM and DMARC stop others sending email that looks like it comes from your domain, a common route to phishing and invoice fraud.

    • Critical

      No email authentication configured

      Domain is vulnerable to email spoofing

      What to do: Implement SPF, DKIM, and DMARC immediately

  2. Security headers

    Security headers are instructions your web server sends to every visitor’s browser. Missing ones leave visitors more exposed to attacks such as clickjacking and injected scripts.

    • High

      Missing X-Frame-Options header

      Prevents clickjacking attacks

      What to do: Add "X-Frame-Options: DENY" or "X-Frame-Options: SAMEORIGIN"

    • High

      Missing Content-Security-Policy header

      Controls resources the browser is allowed to load

      What to do: Implement a Content-Security-Policy appropriate for your application

      • ASVS V3.4.3
      • OWASP Secure Headers: OWASP Secure Headers Project recommends Content-Security-Policy: default-src 'self'; form-action 'self'; base-uri 'self'; object-src 'none';…

  3. GDPR outside view

    These are the privacy signals visitors and data protection authorities look for under GDPR.

    • High

      No Privacy Policy found

      GDPR requires a clear and accessible privacy policy

      What to do: Add a comprehensive privacy policy page and link to it prominently

    • High

      No Cookie Policy found

      GDPR requires clear information about cookie usage

      What to do: Add a dedicated cookie policy explaining cookie usage and purposes

Need hands-on remediation? Email guard@offseq.com

Keep watching highlightjs.org

This scan found 26 issues across 6 checks. Monitoring re-runs those checks daily, emails you when something material changes and records each fix, so you can show progress.

Daily monitoring

Recommended

€25per month

  • TLS certificates and expiry
  • DNS records
  • SPF, DKIM and DMARC
  • Security headers
  • GDPR and NIS2 posture
  • Exposed services
  • Third-party trackers
  • Security score drift

Email alerts on material changes and an exportable JSON history of every change.

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Results by check

Each check with its score, findings and the evidence it collected.

How this score is calculated

The security score runs 0–100, higher is better. It is the plain average of the security checks that completed in this scan, each counted equally. A check that could not run is left out: it counts neither as a pass nor as a fail.

Counted in this score

SSL/TLS
52
Security headers
40
Email security
60
DNS health
70
Network security
100
GDPR outside view
35
Average
60

Not counted

  • NIS2 outside view: Re-weights evidence from the TLS, email, DNS, network and hygiene checks, so counting it would count that evidence twice. Shown on its own.
  • OffSeq Observations: An AI reading of the site, useful context but not reproducible evidence. Shown on its own.

Findings that cap the score at 49

Each of these is serious on its own, so while any is present the site cannot rate better than high risk, however good the other checks are.

  • The certificate is not trusted by browsers
  • The website is not served over HTTPS
  • A database, remote desktop, file-sharing or Telnet service is reachable from the internet
  • The page loads a script from a compromised source
  • The domain registration has expired
  • SPF authorises every server to send mail as the domain

Partial scans

When the site blocks Guard or most checks cannot run, the score covers only the checks that ran (usually DNS and email), is capped at 75 and is shown as partial, without a risk level.

Risk levels

  • Critical0–25
  • High26–49
  • Medium50–75
  • Low76–100

Technical appendix

Business context, site observations and technical notes gathered during the scan, and the standards behind each reference.

Business context

Business profile

Highlight.js occupies a strong position in the developer tools market as a widely adopted syntax highlighter. Its open source nature and GitHub ecosystem foster community engagement and continuous improvement. The project benefits from endorsements by major developer platforms, enhancing credibility. Revenue streams are likely indirect, possibly through sponsorships or donations. The target audience is primarily software developers and technical professionals. The project maintains a lean organizational structure with privacy-protected WHOIS registration, typical for open source initiatives. Strategic partnerships or subsidiaries are not evident. The website content is high quality, consistent, and aligned with the brand identity, supporting effective user engagement and trust.

Security posture

The website demonstrates a moderate to strong security posture with HTTPS enabled and domain status flags preventing unauthorized transfers or updates. However, the absence of DNSSEC and explicit security headers such as Content Security Policy or HSTS reduces defense-in-depth. No vulnerabilities or exposed sensitive data were detected in the content. The availability of a security contact email supports vulnerability disclosure and incident response. Privacy compliance is weak due to missing privacy and cookie policies. Overall, the security maturity is adequate for an open source project website but could be enhanced by adopting additional security best practices and formalizing privacy documentation.

Recommendations

  1. Enable DNSSEC on the domain to improve DNS security and prevent spoofing.
  2. Implement and publish a comprehensive privacy policy and cookie policy to enhance GDPR compliance.
  3. Add standard security headers such as Content Security Policy (CSP), HTTP Strict Transport Security (HSTS), and X-Frame-Options to strengthen web security.
  4. Publish a security.txt file to formalize vulnerability disclosure processes and improve transparency.
  5. Consider adding contact phone numbers or additional contact methods to improve business credibility and user trust.
Site observations

Automated reading of the public site. Ratings are indicative.

Business

Company
Contact Privacy Inc. Customer 0164357247
Description
The Internet's favorite JavaScript syntax highlighter supporting Node.js and the web.
Key services
JavaScript syntax highlighting, Support for 192 languages and 512 themes, Automatic language detection, Compatibility with Node.js, Deno, and any JS framework
Content quality
excellent
Branding
consistent

Technology

Stack
JavaScript, Node.js, Deno, React (Next.js framework), ES6 modules
Frameworks
Next.js
Platforms
Web, Node.js, Deno
Performance
fast
Mobile
excellent
Accessibility
good
SEO
good

Security

Observed score
80/100
Good practices seen
  • HTTPS enforced (implied by https URL)
  • Domain status includes clientTransferProhibited and clientUpdateProhibited
  • Security contact email provided

Analytics and tracking

Tracking level
minimal
Privacy practices
poor

Advertising

Transparency
poor

Site quality

Design
excellent
User experience
excellent
Content relevance
excellent
Navigation
excellent
Professionalism
excellent
Trustworthiness
high

Key observations

  1. Website is a professional open source project site
  2. No privacy or cookie policies found
  3. Security contact email provided for vulnerability reporting
  4. No forms detected on the main page
  5. No explicit security headers detected in HTML content
  6. Uses modern web technologies and hosting
  7. Trusted by major developer platforms
Technical notes

Notes

The website is built using modern JavaScript frameworks, specifically Next.js, leveraging server-side rendering and static generation for performance. Hosting on Netlify ensures fast content delivery and scalability. The tech stack includes support for Node.js and Deno environments, reflecting a modern developer-centric approach. The site is mobile-optimized with responsive design and good accessibility features. No CMS was detected, indicating a custom or static site approach. Performance is fast with preloading of CSS and deferred JavaScript loading. However, the lack of explicit security headers and privacy policies indicates some technical debt in security and compliance areas. Overall, the technical infrastructure is robust and well-suited for the target audience.
Standards and sources

Reference chips under each finding point to the standard, regulation or specification the finding relates to. They are taken from the official datasets below and mapped conservatively: a finding with no defensible link shows none. NIS2 and GDPR references mark where a finding is relevant evidence, not a compliance verdict. Implementing Regulation (EU) 2024/2690 binds digital infrastructure and digital service providers; for other entities it is the most detailed public reading of the Article 21 measures. WCAG, EN 301 549, European Accessibility Act and Web Accessibility Directive references name the requirement an automated accessibility rule relates to; they are not a conformance verdict.

Retrieved 2026-10-25

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