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Security report for jslint.com

Technology · N/a

Medium risk. 8 critical or high findings in Email security, Security headers and 2 other checks.

Security score

61/100

Risk levelMedium

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

JSLint.com is the official website for JSLint, a JavaScript code quality and coverage tool authored by Douglas Crockford. The website provides an in-browser linting tool that analyzes JavaScript code without sending it over the network, emphasizing privacy and local execution. The site links to its GitHub repository and related resources, positioning itself as a trusted open source developer utility in the JavaScript ecosystem. The business model is primarily open source and community-driven, targeting JavaScript developers seeking code quality assurance.

Scanned

NIS2 and GDPR posture

GDPR outside view
50/ 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

8 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 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';…

  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

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

Keep watching jslint.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

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  • 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
72
Security headers
15
Email security
60
DNS health
70
Network security
100
GDPR outside view
50
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 serves a niche technical audience of JavaScript developers and programmers. It leverages open source principles with no evident commercial transactions on the site itself, though it links to a book for purchase. The presence of GitHub links and absence of commercial contact details suggest a community-supported project rather than a commercial enterprise. The market position is strong within the JavaScript linting tools segment due to its historical significance and author reputation. No partnerships or subsidiaries are evident from the site content.

Security posture

The security posture is moderate; the site runs entirely in-browser linting without transmitting user code, which is a strong privacy feature. However, no security headers were detected in the provided data, and the example code uses eval(), which triggers lint warnings and could be a security concern if replicated in user code. The lack of privacy, cookie, and incident response policies reduces compliance maturity. No forms or user data collection reduce attack surface. WHOIS data is unavailable, which may raise trust questions about domain registration status.

Recommendations

  1. Implement and publish privacy and cookie policies to improve compliance and user trust.
  2. Add security headers such as Content-Security-Policy and X-Frame-Options to enhance security posture.
  3. Remove or replace eval() usage in example code to avoid security warnings and potential vulnerabilities.
  4. Verify and update WHOIS domain registration to ensure transparency and legitimacy.
  5. Provide contact and incident response information to improve security readiness and user support.
Site observations

Automated reading of the public site. Ratings are indicative.

Business

Description
JSLint is a JavaScript code quality and coverage tool that runs in the browser without sending code over the network.
Key services
JavaScript code quality analysis, Linting and reporting of JavaScript code issues
Content quality
good
Branding
consistent

Technology

Stack
JavaScript, CodeMirror, ES Modules, HTML5, CSS3
Platforms
Browser
Performance
fast
Mobile
basic
Accessibility
basic
SEO
basic

Security

Observed score
75/100
Good practices seen
  • Runs linting locally in browser without sending code over network
  • No forms or user data collection

Analytics and tracking

Tracking level
minimal
Privacy practices
poor

Advertising

Transparency
poor

Site quality

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

Key observations

  1. Website is a functional JavaScript linting tool running entirely in browser
  2. No privacy, cookie, or terms of service policies found
  3. No contact or business registration information provided
  4. No forms or user data collection present
  5. Use of eval() in example code triggers lint warning
  6. No security headers detected in provided data
  7. No WHOIS data available, domain may be unregistered or WHOIS blocked
  8. External links to GitHub and Amazon for instructions and book purchase
  9. No advertising or tracking technologies detected
Technical notes

Notes

The website uses modern web technologies including ES modules, CodeMirror for code editing, and runs fully client-side JavaScript linting. The design is clean and functional with good performance and basic mobile optimization. Accessibility features are present but could be improved. SEO is basic with meta description and author tags but no structured data or Open Graph tags. No CMS or hosting provider information is evident. The site does not use analytics or tracking technologies, enhancing privacy. Technical debt appears low, but security best practices could be strengthened.
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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