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Security report for kleppmann.com

Martin Kleppmann · Education · United Kingdom

Medium risk. 6 critical or high findings in Security headers, GDPR outside view and 1 other check.

Security score

61/100

Risk levelMedium

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

Dr. Martin Kleppmann's website serves as a comprehensive academic and professional platform showcasing his work as an Associate Professor at the University of Cambridge. The site highlights his research focus on local-first collaboration software and distributed systems security, his teaching activities, open source contributions, and a well-regarded book on data-intensive applications. The website targets academics, researchers, students, and professionals interested in distributed systems and cryptography. It also supports his research through Patreon and promotes his publications and conference talks. Technically, the website is built using Jekyll, with a clean and professional design that is mobile-optimized and accessible. It uses standard web technologies including HTML5, CSS3, JavaScript, and MathJax for mathematical rendering. The site performs well with fast loading times and clear navigation. However, it lacks some modern security headers and explicit HTTPS enforcement details are not available from the provided data. From a security perspective, the site does not expose sensitive data or use vulnerable libraries. There are no forms collecting sensitive user data, which reduces attack surface. However, the absence of privacy and cookie policies, security incident response information, and vulnerability disclosure mechanisms indicates gaps in compliance and security transparency. The WHOIS data for the domain is missing, which is unusual and reduces trustworthiness, though the professional nature of the content suggests legitimacy. Overall, the website is a high-quality academic resource with excellent content and user experience but could improve in privacy compliance and security transparency. The missing WHOIS data is a concern that should be investigated further to confirm domain legitimacy.

Scanned

NIS2 and GDPR posture

GDPR outside view
53/ 100 · Medium
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

6 findings rated critical or high. Fix these first.

  1. 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 Strict-Transport-Security header

      Forces HTTPS connections

      What to do: Add "Strict-Transport-Security: max-age=31536000; includeSubDomains; preload"

      • CWE-319
      • OWASP A04:2025
      • ASVS V3.4.1
    • 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';…

  2. GDPR outside view

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

    • 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

    • High

      No Cookie Consent Banner found

      GDPR requires explicit consent for non-essential cookies

      What to do: Implement a cookie consent banner that appears on first visit

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

Keep watching kleppmann.com

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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Full report

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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
65
Security headers
15
Email security
60
DNS health
75
Network security
100
GDPR outside view
53
Average
61

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

The website positions Dr. Martin Kleppmann as a leading academic and researcher in distributed systems and cryptography. His competitive advantage lies in his authoritative publications, including a popular book and numerous peer-reviewed papers, as well as his involvement in open source projects and conference speaking engagements. The business model is primarily academic dissemination and personal branding, supplemented by book sales and Patreon support. The target customers are academics, students, and professionals in technology and education sectors. Growth indicators include ongoing publications, upcoming book editions, and active participation in conferences. The partnership ecosystem includes academic institutions and open source communities. Strategic observations note a strong reputation and trustworthiness but highlight the need for improved privacy and security policies to align with modern compliance standards.

Security posture

The website demonstrates a moderate security maturity level. It benefits from minimal attack surface due to lack of forms and sensitive data collection. However, the absence of security headers, privacy and cookie policies, and incident response information indicates gaps in security best practices and compliance. The missing WHOIS data is a notable concern that impacts trust and domain legitimacy assessment. There is no evidence of vulnerabilities or malware, but the site would benefit from implementing security headers, HTTPS enforcement, and publishing a security policy. Compliance with GDPR and other data protection regulations is not evident, which could pose risks if personal data collection increases in the future. Incident response readiness and vulnerability disclosure mechanisms are absent, limiting transparency and trust.

Recommendations

  1. Implement and enforce HTTPS with strong TLS configuration and verify SSL certificates.
  2. Add comprehensive privacy and cookie policies with clear GDPR compliance statements.
  3. Publish a security policy and vulnerability disclosure page to improve transparency.
  4. Add security headers such as Content-Security-Policy, X-Frame-Options, and Strict-Transport-Security.
  5. Investigate and resolve missing WHOIS data to improve domain legitimacy and trust.
Site observations

Automated reading of the public site. Ratings are indicative.

Business

Company
Martin Kleppmann
Description
Personal academic and professional website of Dr. Martin Kleppmann, Associate Professor at University of Cambridge, focusing on local-first collaboration software, distributed systems security, teaching, research, and publications including a well-known book on data-intensive applications.
Key services
Academic research, Teaching, Open source software development, Book publication, Public speaking and conference talks
Content quality
excellent
Branding
consistent

Technology

Stack
HTML5, CSS3, JavaScript, MathJax, Jekyll
Frameworks
Jekyll
Performance
fast
Mobile
good
Accessibility
good
SEO
good

Security

Observed score
70/100
Good practices seen
  • No forms with sensitive inputs detected
  • No exposed sensitive data in HTML

Analytics and tracking

Tracking level
minimal
Privacy practices
poor

Advertising

Transparency
basic

Site quality

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

Key observations

  1. Website is a personal academic site for Dr. Martin Kleppmann.
  2. Content is rich with publications, talks, and research information.
  3. No privacy or cookie policies found.
  4. No security or incident response policies published.
  5. No contact phone numbers or physical addresses found.
  6. No forms collecting user data detected.
  7. No analytics or tracking scripts detected.
  8. No WAF or blocking mechanisms detected.
  9. WHOIS data is missing or unavailable, which is unusual for a .com domain.
Technical notes

Notes

The website is built on a static site generator (Jekyll) with clean HTML5 and CSS3, enhanced by JavaScript and MathJax for mathematical content. It has a fast performance profile and is mobile-optimized with good accessibility features. The site uses external resources hosted on reputable domains. There is no evidence of heavy analytics or tracking scripts, which supports privacy. The technical stack is modern but could be improved with additional security headers and HTTPS enforcement verification. The lack of dynamic forms reduces complexity and security risks but also limits interactive capabilities. Overall, the technical infrastructure is solid for an academic personal website but could benefit from enhanced security and privacy features.
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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