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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

Cloverleaf is a well-established language school based in Ostrava, Czech Republic, operating since 1993. It offers a broad range of language courses including general English, Cambridge exam preparation, e-learning, and specialized courses for children, youth, and professionals. The school positions itself as the largest in the region with a strong focus on quality teaching, modern facilities, and comprehensive student support services. The website is professionally designed, mobile-optimized, and provides clear navigation and rich content to serve its diverse audience effectively. Technically, the site uses modern web technologies including Bootstrap, Google Analytics, and Facebook SDK, hosted on REG-ZONER infrastructure. Security posture is solid with HTTPS enforced and cookie consent mechanisms in place, though some security headers could be improved. Privacy compliance is strong with clear policies and GDPR-aligned consent. Overall, the business demonstrates credibility and trustworthiness with transparent contact information and certifications from relevant language school associations.

Scanned

This is an earlier scan of cloverleaf.cz. View the latest report

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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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
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

The company operates in the education sector, specifically language training, targeting individuals, companies, and educators in the Czech Republic. Its business model revolves around providing in-person and online language education, exam preparation, and supplementary services like translation and language audits. The company benefits from a strong regional market position as the largest language school in Ostrava, supported by a professional teaching staff and modern infrastructure. Partnerships with ISSA CZECH and membership in the Asociace jazykových škol enhance its credibility. Revenue streams likely include course fees, exam fees, e-learning subscriptions, and sales from the associated e-shop. The presence of a newsletter and active social media channels indicates ongoing customer engagement and marketing efforts.

Security posture

The website enforces HTTPS and uses cookie consent mechanisms to comply with privacy regulations. It integrates third-party analytics and marketing tools responsibly with user consent. No critical vulnerabilities or exposed sensitive data were detected in the HTML content. However, the absence of explicit HTTP security headers such as Content Security Policy (CSP), HSTS, and X-Frame-Options suggests room for improvement. There is no visible security or incident response policy or dedicated security contact information. Overall, the security posture is good but could be enhanced by implementing additional HTTP headers and publishing incident response details.

Recommendations

  1. Implement HTTP security headers including CSP, HSTS, X-Frame-Options, and X-XSS-Protection to strengthen defense against common web attacks.
  2. Publish a dedicated security policy and provide incident response contact information to improve transparency and preparedness.
  3. Regularly audit and update third-party scripts and libraries to mitigate potential vulnerabilities.
  4. Enhance accessibility features to improve compliance and user experience for all visitors.
  5. Maintain and update privacy and cookie policies to reflect evolving regulations and best practices.

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 širokou škálu jazykových kurzů, přípravu na mezinárodní zkoušky Cambridge, e-learning, vzdělávání pedagogů a doplňkové služby jako překlady a tlumočení.
Key services
Jazykové kurzy pro veřejnost, Jazykové zkoušky Cambridge, E-learning, Vzdělávání pedagogů, Překlady a tlumočení, Rozřazovací testy, E-shop s učebnicemi
Content quality
good
Branding
consistent

Technology

Stack
HTML5, CSS3, JavaScript, jQuery, Bootstrap, Google Analytics, Facebook SDK, Google Tag Manager
Frameworks
Bootstrap
Performance
moderate
Mobile
good
Accessibility
basic
SEO
good

Security

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

Analytics and tracking

Services
Google Analytics, Google Tag Manager
Tracking level
moderate
Privacy practices
good

Advertising

Ad networks
Google AdWords, Seznam retargeting
Tracking pixels
Facebook Pixel
Marketing tools
Facebook SDK
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 rich content.
  2. Comprehensive cookie consent and privacy mechanisms implemented.
  3. Multiple language course offerings with detailed descriptions.
  4. Use of reputable third-party analytics and marketing tools with consent.
  5. Clear contact information and business legitimacy indicators.
  6. No signs of security blocking or WAF interference.
  7. Good technical implementation with room for security header improvements.
Technical notes

Notes

The website is built using a modern tech stack with HTML5, CSS3, JavaScript, jQuery, and Bootstrap framework. It leverages Google Analytics and Facebook SDK for analytics and marketing. The CMS Designer platform is used for content management. Hosting is provided by REG-ZONER, a reputable Czech hosting provider. The site is mobile-optimized and performs moderately well, though no explicit performance metrics were available. The site structure and metadata are well implemented, supporting SEO and user navigation. Technical debt appears low, but security header implementation and accessibility improvements are recommended to reduce risks and enhance user experience.
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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