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Security report for cloverleaf.cz

ISSA CZECH s.r.o. · Education · Czech Republic

Medium risk. 7 critical or high findings in GDPR outside view, Security headers and 2 other checks.

Security score

61/100

Risk levelMedium

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

Jazyková škola Cloverleaf Ostrava is a well-established language school operating since 1993, offering a wide range of language courses including English, Cambridge exam preparation, e-learning, and specialized courses for children, youth, and corporate clients. The school positions itself as the largest language school in the Ostrava region with a strong focus on quality teaching, modern facilities, and professional staff. The website reflects a mature digital presence with clear navigation, responsive design, and comprehensive content tailored to its target audience of students and professionals seeking language education. Technically, the website employs modern web technologies including Bootstrap for responsive design, Google Analytics and Tag Manager for analytics, and Facebook Pixel for marketing. Cookie consent is implemented with express consent and granular preference management, demonstrating good privacy compliance. Hosting is managed by REG-ZONER, a reputable Czech registrar and hosting provider, consistent with the domain's WHOIS data. From a security perspective, the site enforces HTTPS and uses secure login forms. However, it lacks explicit HTTP security headers and does not provide a dedicated security policy or incident response contact, which are areas for improvement. No vulnerabilities or exposed sensitive data were detected in the HTML content. The domain's WHOIS data is consistent with the business claims, showing a long domain age and no privacy protection, supporting legitimacy. Overall, the website is professional, trustworthy, and compliant with GDPR requirements. Strategic recommendations include enhancing security headers, publishing a security policy, and providing incident response contacts to further strengthen security posture and user trust.

Scanned

NIS2 and GDPR posture

GDPR outside view
40/ 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

7 findings rated critical or high. Fix these first.

  1. GDPR outside view

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

    • Critical

      EU business without adequate privacy measures

      EU businesses are subject to strict GDPR requirements

      What to do: Implement comprehensive GDPR compliance including privacy policy, cookie consent, and data protection measures

    • 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

      Third-party services without privacy policy

      Detected services: Google Analytics, Facebook, Twitter, LinkedIn, YouTube

      What to do: Document all third-party data sharing in your privacy policy

  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 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';…

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Keep watching cloverleaf.cz

This scan found 24 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.

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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
67
Security headers
35
Email security
60
DNS health
65
Network security
100
GDPR outside view
40
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

Cloverleaf operates in the education sector, specifically language education, with a strong regional presence in Ostrava, Czech Republic. The company leverages a diversified business model offering public language courses, Cambridge exam preparation, e-learning, corporate training, and translation services. Its competitive advantage lies in its long-standing market presence, comprehensive course offerings, and membership in the Asociace jazykových škol, which enhances credibility. Revenue streams likely include course fees, exam fees, and supplementary services such as translation and audits. The target customer segments include students, working professionals, companies, and educators. The partnership ecosystem includes ISSA CZECH s.r.o. (developer/publisher), Cloverbooks e-shop, and industry associations. The company shows indicators of stable growth and digital maturity through its integrated marketing and analytics tools.

Security posture

The website demonstrates a moderate to strong security posture with enforced HTTPS, secure login forms, and a robust cookie consent mechanism aligned with GDPR. The use of multiple tracking and advertising scripts is managed with user consent, reflecting privacy awareness. However, the absence of HTTP security headers such as Content Security Policy, HSTS, and X-Frame-Options reduces defense-in-depth. No incident response or security policy information is publicly available, which may hinder rapid response to security events. No vulnerabilities or sensitive data leaks were detected in the analyzed content. Overall, the security maturity is good but can be improved by implementing recommended headers and publishing security policies.

Recommendations

  1. Implement HTTP security headers including Content Security Policy (CSP), HTTP Strict Transport Security (HSTS), X-Frame-Options, and X-Content-Type-Options to enhance protection against common web attacks.
  2. Publish a dedicated security policy page outlining security practices and incident response procedures to improve transparency and trust.
  3. Provide clear incident response contact channels such as security@ or abuse@ email addresses to facilitate reporting and handling of security incidents.
  4. Regularly audit and update third-party scripts and tracking technologies to minimize vulnerabilities and ensure compliance with privacy regulations.
  5. Enhance accessibility features and conduct periodic security assessments to maintain high standards of security and user experience.

Contact details published on the site

Addresses
Legal name
ISSA CZECH s.r.o.
Site observations

Automated reading of the public site. Ratings are indicative.

Business

Company
ISSA CZECH s.r.o.
Description
Jazyková škola Cloverleaf Ostrava je největší jazyková škola v regionu s tradicí od roku 1993. Nabízí široký výběr jazykových kurzů, včetně angličtiny, přípravy na Cambridge zkoušky, e-learningu, kurzů pro děti, mládež i firmy. Disponuje kvalitním lektorským týmem, moderním technickým zázemím a profesionálním personálem. Poskytuje služby i mimo Ostravu, např. v Opavě a Frýdku-Místku.
Key services
jazykové kurzy pro veřejnost, Cambridge zkoušky, e-learning, kurzy pro děti a mládež, firemní výuka, překlady a tlumočení, jazykový audit
Content quality
good
Branding
consistent

Technology

Stack
Google Analytics, Google Tag Manager, Facebook Pixel, Seznam Retargeting, Bootstrap CSS, jQuery, CMS Designer
Frameworks
Bootstrap
Performance
moderate
Mobile
good
Accessibility
basic
SEO
good

Security

Observed score
85/100
Good practices seen
  • HTTPS enforced
  • Cookie consent with granular control
  • No exposed sensitive data in HTML
  • Secure login form with password field

Analytics and tracking

Services
Google Analytics, Google Ads Conversion Tracking
Tracking level
moderate
Privacy practices
good

Advertising

Ad networks
Google Ads, Seznam Retargeting
Tracking pixels
Facebook Pixel
Transparency
good

Site quality

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

Key observations

  1. Website is fully accessible with no blocking or WAF challenges.
  2. Comprehensive cookie consent mechanism implemented with express consent and granular preferences.
  3. Multiple Google Analytics and advertising scripts present with consent management.
  4. Clear business contact information including phone, email, and physical address.
  5. Professional design with responsive layout and clear navigation.
  6. No security headers detected in HTML but HTTPS is enforced.
  7. No explicit security or incident response policies found on site.
  8. WHOIS data supports legitimacy and long-term operation.
  9. Social media presence on Facebook, Twitter, YouTube, LinkedIn.
  10. No adult or questionable content detected.
Technical notes

Notes

The website is built on a CMS Designer platform with Bootstrap framework for responsive design. It uses modern analytics and marketing tools including Google Analytics, Google Tag Manager, Facebook Pixel, and Seznam Retargeting. The site is hosted by REG-ZONER, a reputable Czech hosting provider. Performance is moderate with good mobile optimization and basic accessibility features. SEO is supported by proper meta tags and structured navigation. The site uses multiple external scripts loaded asynchronously to optimize load times. There is room for technical improvement by adding security headers and enhancing accessibility compliance. Overall, the technical infrastructure supports the business needs effectively with opportunities for modernization.
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. 61/100Medium33 findingsView report
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