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Security report for codepen.io

CodePen · Technology · United States

Low risk. 4 critical or high findings in Security headers, GDPR outside view and 1 other check.

Security score

76/100

Risk levelLow

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

CodePen is a well-established online platform founded in 2012 that serves as a social development environment for front-end developers and designers. It offers an online code editor, project building, testing, and a vibrant community for sharing and discovering front-end code snippets and projects. The platform operates on a freemium business model with PRO accounts and team subscriptions, positioning itself as a leader in the front-end development community. The website is professionally designed, mobile-optimized, and provides clear navigation and rich content that caters to its target audience of front-end developers and designers. Technically, CodePen employs modern web technologies including React, SCSS, and JavaScript, hosted and protected by Cloudflare services. The site demonstrates good performance, accessibility, and SEO optimization. Security measures include HTTPS enforcement and CSRF protection in forms, although DNSSEC is not enabled and some security headers are not explicitly detected. Privacy policies and terms of service are comprehensive and publicly accessible, though a cookie consent mechanism and explicit security policies are absent. From a security perspective, CodePen maintains a strong posture with encrypted communications and domain registration consistency. However, improvements can be made by enabling DNSSEC, publishing a security policy, and implementing cookie consent to enhance GDPR compliance. No critical vulnerabilities or blocking mechanisms were detected, and the site is safe for general audiences. Overall, CodePen is a credible, professional, and secure platform with minor areas for enhancement in privacy compliance and DNS security. Strategic recommendations include enabling DNSSEC, adding cookie consent, publishing security and incident response policies, and enhancing security headers to further strengthen trust and compliance.

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

4 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 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

  3. SSL/TLS

    TLS encrypts the connection and proves the site is really yours. Weak or expiring certificates trigger browser warnings and put traffic at risk.

    • High

      Weak SSL Key Length

      SSL certificate uses 256-bit key, which is considered weak

      What to do: Use at least 2048-bit RSA or 256-bit ECC key

      • CWE-326
      • OWASP A04:2025
      • Mozilla TLS: Mozilla Server Side TLS 6.0 intermediate: rsa_key_size 2048

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

Keep watching codepen.io

This scan found 16 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

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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
70
Email security
85
DNS health
80
Network security
100
GDPR outside view
53
Average
76

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

CodePen holds a strong market position as a leading front-end development platform with a large user base and active community. Its freemium model with PRO and Teams offerings provides diversified revenue streams. The platform's partnership with MongoDB Atlas and use of reputable advertising networks indicate a mature partnership ecosystem. The company targets front-end developers and designers globally, with a focus on innovation, collaboration, and learning. Growth indicators include active challenges, community engagement, and continuous feature enhancements. The business model leverages community-driven content and premium subscriptions, positioning CodePen as a key player in the developer tools market.

Security posture

CodePen exhibits a mature security posture with HTTPS enforced site-wide, CSRF token usage in forms, and domain registration protections such as clientTransferProhibited status. The absence of DNSSEC is a minor gap that could be addressed to prevent DNS spoofing. No exposed sensitive data or vulnerable libraries were detected in the provided content. The lack of a published security policy or incident response contact limits transparency and may impact trust for security-conscious users. GDPR compliance is supported by a comprehensive privacy policy, but the absence of a cookie consent mechanism is a compliance gap. Overall, the platform demonstrates good security hygiene with room for improvement in transparency and DNS security.

Recommendations

  1. Enable DNSSEC on the domain to enhance DNS security and prevent spoofing.
  2. Implement a cookie consent mechanism to comply fully with GDPR and other privacy regulations.
  3. Publish a formal security policy and incident response contact information to improve transparency and trust.
  4. Add security headers such as Content-Security-Policy and X-Frame-Options to strengthen browser security.
  5. Consider publishing a vulnerability disclosure policy or security.txt file to encourage responsible reporting.
Site observations

Automated reading of the public site. Ratings are indicative.

Business

Company
CodePen
Description
CodePen is a social development environment for front-end designers and developers. It allows users to build, share, and learn JavaScript, CSS, and HTML with an online code editor. Users can build and deploy websites, show off their work, build test cases to learn and debug, and find inspiration.
Key services
Online code editor, Project building and testing, Community sharing and discovery, Challenges and learning, PRO accounts with private projects, Team collaboration features
Content quality
excellent
Branding
consistent

Technology

Stack
React, SCSS, JavaScript, Cloudflare DNS, Firebase
Frameworks
React
Platforms
Web
Performance
fast
Mobile
excellent
Accessibility
good
SEO
good

Security

Observed score
85/100
Good practices seen
  • HTTPS enforced
  • CSRF tokens present in forms
  • Client transfer prohibited domain status

Analytics and tracking

Tracking level
moderate
Privacy practices
basic

Advertising

Ad networks
Carbon Ads, BuySellAds
Transparency
good

Site quality

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

Key observations

  1. Website is fully accessible with rich content and interactive features.
  2. Strong branding and consistent design across pages.
  3. No direct company contact emails or phone numbers found on the homepage.
  4. Privacy and terms policies are clearly linked and comprehensive.
  5. No explicit cookie consent mechanism detected.
  6. Use of modern web technologies and frameworks.
  7. No security.txt or explicit vulnerability disclosure policy found.
  8. DNSSEC not enabled, which is a minor security gap.
  9. Advertising is present but transparent and limited to reputable networks.
Technical notes

Notes

The website is built using modern front-end technologies including React and SCSS, ensuring a responsive and interactive user experience. Hosting and DNS services are provided by Cloudflare, offering performance and security benefits. The site loads quickly and is optimized for mobile devices, with good accessibility features. The use of Firebase indicates integration with cloud services for backend or data storage needs. No CMS was detected, suggesting a custom-built platform. Technical debt appears minimal with a clean and modular codebase. Opportunities exist to enhance security headers and DNS configurations to further reduce technical risks.
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

Earlier scans of this domain

  1. 76/100Low24 findingsView report
  2. 76/100 −3Low24 findingsView report
  3. 79/100Low19 findingsView report
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