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Security report for crossref.cz

Solen Software, s.r.o. · Education · Czech Republic

Medium risk. 7 critical or high findings in GDPR outside view, Security headers and 1 other check.

Security score

55/100

Risk levelMedium

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

The website crossref.cz serves as an educational and informational portal focused on the CrossRef system, DOI identifiers, and scientific databases, primarily targeting the Czech academic and research community. It provides clear explanations about CrossRef as a reference linking system and DOI as a persistent digital identifier, linking to official CrossRef and DOI websites. The site is operated by Solen Software, s.r.o., a Czech company, and uses a Czech hosting provider, reflecting a consistent regional focus. From a technical perspective, the site employs legacy JavaScript libraries such as jQuery 1.7.2 alongside modern analytics tools like Google Analytics and Google Tag Manager. The content is well-structured with professional design and navigation, though mobile optimization and accessibility are basic. The site uses the Actavia editorial system and is hosted on Aerohosting servers. Performance is moderate, with no critical technical issues detected. Security posture is moderate but could be improved. The site lacks HTTPS confirmation in the provided data, no explicit security headers were detected, and no privacy or cookie policies are present, indicating gaps in compliance with GDPR and modern security best practices. No forms or sensitive data collection points reduce immediate risk, but the absence of contact and incident response information limits transparency. Overall, the website is a legitimate, niche educational resource with consistent WHOIS data and a stable domain age. However, it would benefit from enhanced privacy compliance, security hardening, and clearer contact information to improve trust and regulatory adherence.

Scanned

NIS2 and GDPR posture

GDPR outside view
10/ 100 · Critical
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

      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

  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 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';…

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

Keep watching crossref.cz

This scan found 22 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
62
Security headers
70
Email security
70
DNS health
75
Network security
40
GDPR outside view
10
Average
55

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

Breach exposure

Leaked credentials and lookalike domains from OffSeq Breach. The counts are free; the detailed lists are paid add-ons.

Dark web exposure

Add-on

Leaked records that mention crossref.cz, from OffSeq Breach.

No leaked records found

Breach holds no records for crossref.cz right now. New leaks arrive continuously, so monitoring on Breach alerts you if that changes.

Monitor on Breach (opens in a new tab)

Technical appendix

Business context, site observations and technical notes gathered during the scan, and the standards behind each reference.

Business context

Business profile

Crossref.cz operates as a specialized educational platform providing information about DOI and CrossRef systems, targeting researchers, academic publishers, and librarians primarily in the Czech Republic. Its competitive advantage lies in localized content and clear linkage to official DOI and CrossRef resources. The business model appears informational rather than transactional, supporting academic referencing and publishing workflows. Revenue streams are not explicit but may derive from software services by Solen Software or partnerships. The partnership ecosystem includes Actavia (editorial system) and Solen Software (developer and copyright holder). Growth indicators are limited due to niche focus, but the site maintains a stable presence since 2012. Strategic observations suggest opportunities to expand compliance transparency and enhance user engagement through contact and policy disclosures.

Security posture

The website demonstrates a basic security maturity level with no visible critical vulnerabilities or exposed sensitive data. However, the absence of HTTPS confirmation, security headers, and privacy/cookie policies indicates compliance and security gaps. The lack of incident response contact channels and vulnerability disclosure mechanisms reduces readiness for security events. Use of older JavaScript libraries may pose potential risks if not regularly updated. The site does not collect user data via forms, minimizing attack surface. Overall, security practices are minimal and should be enhanced to meet GDPR and modern web security standards.

Recommendations

  1. Implement HTTPS with a valid SSL/TLS certificate and enforce secure connections site-wide.
  2. Add comprehensive privacy and cookie policies with clear GDPR compliance statements.
  3. Deploy security headers such as Content-Security-Policy, X-Frame-Options, and X-Content-Type-Options.
  4. Provide clear contact information including security incident response and data protection officer details.
  5. Update JavaScript libraries to supported versions and conduct regular security audits.
Site observations

Automated reading of the public site. Ratings are indicative.

Business

Company
Solen Software, s.r.o.
Description
Website dedicated to the CrossRef system, DOI identifiers, and scientific databases. It provides information about CrossRef as an independent reference system linking citations and electronic journal articles, and about DOI as a unique and permanent international identifier for digital objects such as online publications.
Key services
Information about CrossRef, Information about DOI, Links to official CrossRef and DOI websites, Information about scientific databases
Content quality
good
Branding
consistent

Technology

Stack
jQuery 1.7.2, jQuery UI 1.12.1, Modernizr, Google Analytics, Google Tag Manager, ISCroll
Performance
moderate
Mobile
basic
Accessibility
basic
SEO
basic

Security

Observed score
55/100
Good practices seen
  • No forms detected to collect sensitive data
  • No exposed credentials or sensitive data in HTML

Analytics and tracking

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

Advertising

Transparency
basic

Site quality

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

Key observations

  1. Website is an informational resource about CrossRef and DOI in Czech language.
  2. No privacy, cookie, or terms of service policies found.
  3. No contact emails or phone numbers explicitly provided on the site.
  4. Uses older versions of jQuery but includes modern analytics tools.
  5. No forms detected, reducing risk of data collection vulnerabilities.
  6. No explicit security headers detected in provided data.
  7. Site uses a Czech hosting provider with consistent WHOIS data.
  8. No adult or questionable content detected.
  9. Site branding and logos are consistent and professional.
  10. Google Analytics and Tag Manager are used for tracking without visible consent mechanisms.
Technical notes

Notes

The website uses a legacy JavaScript stack with jQuery 1.7.2 and jQuery UI 1.12.1, supplemented by Modernizr and iScroll for UI enhancements. Google Analytics and Google Tag Manager are integrated for user tracking. The CMS is Actavia, a Czech editorial system, hosted on Aerohosting servers with Czech name servers. The site has moderate performance and basic mobile optimization. SEO is basic with meta tags present but no advanced structured data or Open Graph tags detected. Accessibility features are minimal. Technical debt is present due to older libraries and lack of modern security headers. Modernization opportunities include upgrading libraries, improving mobile responsiveness, and adding structured data for SEO enhancement.
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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