Skip to main content

Security report for eso.org

European Southern Observatory · Government · N/a

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

Security score

69/100

Risk levelMedium

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

The European Southern Observatory (ESO) is a leading intergovernmental organization dedicated to astronomical research and the operation of world-class ground-based observatories in the Southern Hemisphere. The website serves as a comprehensive portal for scientific discoveries, public outreach, educational resources, and detailed information about ESO's telescopes and instruments. It targets a broad audience including researchers, educators, students, and astronomy enthusiasts worldwide. The business model is non-profit and government-oriented, focusing on advancing astronomy and related technologies. Technically, the website employs modern web technologies including HTML5, CSS3, JavaScript, jQuery, and integrates Matomo analytics for privacy-conscious visitor tracking. It is hosted on CDN77, ensuring fast content delivery and good performance. The site is mobile-optimized, accessible, and SEO-friendly, with clear navigation and multilingual support. From a security perspective, the site enforces HTTPS, uses CSRF tokens, and implements cookie consent mechanisms aligned with GDPR. While explicit security headers like Content-Security-Policy are not confirmed, best practices are largely followed. No vulnerabilities or exposed sensitive data were detected. However, the absence of a public security policy or vulnerability disclosure program is noted. Overall, the website presents a low-risk profile with strong trust indicators and professional content. The lack of WHOIS data limits domain registration insights but does not detract from the site's legitimacy. Strategic recommendations include enhancing security header implementation, publishing a security policy, and establishing a vulnerability disclosure channel to further strengthen trust and compliance.

Scanned

NIS2 and GDPR posture

GDPR outside view
73/ 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 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';…

  2. GDPR outside view

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

    • 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 Protocols Supported

      Server supports weak protocols: TLSv1.1

      What to do: Disable TLS 1.0, TLS 1.1, and all SSL versions

      • CWE-327
      • OWASP A04:2025
      • ASVS V12.1.1

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

Keep watching eso.org

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.

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.

Billed monthly to your card. Cancel anytime. The full timeline opens with your unlock code.

Full report

€39.90one-time

  • The complete analysis as a PDF you can cite
  • Email delivery with an unlock code
  • Lifetime access to this report

Prices incl. 21% VAT. Secure checkout by Mollie; sold by SEQ SIA, Latvia.

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
25
Email security
75
DNS health
75
Network security
100
GDPR outside view
73
Average
69

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 eso.org, from OffSeq Breach.

Total records
622
Employees
2
Customers
598
Third parties
22
Weak passwords
0%

Latest record dated 2025-04-14 · 52 subdomains affected

See the 10 newest leaked credentials

A one-off add-on to this report that lists the most recent identifier and password pairs OffSeq Breach holds for eso.org.

Select it in the checkout above.

Masked preview

  • –email.eso.org2025-04-14
  • –email.eso.org2025-04-14

Breach keeps ingesting new leaks, so these numbers can grow between scans.

Open in Breach(opens in a new tab)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

ESO holds a dominant position in the astronomical research sector, operating premier observatories such as the Very Large Telescope (VLT) and ALMA. Its competitive advantage lies in its intergovernmental status, access to cutting-edge technology, and extensive public engagement. Revenue streams are primarily government funding and partnerships. The target customers include scientific communities, educational institutions, and the general public interested in space science. Growth indicators include continuous technological upgrades and active outreach programs. The partnership ecosystem includes collaborations with industry and educational bodies. Operationally, ESO maintains a high standard of professionalism and transparency, reflected in its comprehensive online presence and multilingual content.

Security posture

ESO's website demonstrates a mature security posture with mandatory HTTPS, CSRF protection, and GDPR-compliant cookie management. The use of reCAPTCHA protects forms from spam and abuse. No critical vulnerabilities or exposed sensitive information were found. However, the absence of a published security policy, incident response plan, or vulnerability disclosure mechanism suggests room for improvement in transparency and readiness. Compliance with GDPR is evident, but additional certifications or frameworks like ISO 27001 are not mentioned. Incident response contact channels are not publicly listed, which could hinder timely communication in case of security events.

Recommendations

  1. Implement and publish a comprehensive Content-Security-Policy header to mitigate cross-site scripting risks.
  2. Develop and make publicly available a security policy and incident response plan to enhance transparency and preparedness.
  3. Establish a vulnerability disclosure program or security.txt file to encourage responsible reporting of security issues.
  4. Consider obtaining recognized security certifications such as ISO 27001 to strengthen compliance and trust.
  5. Enhance contact information with dedicated security or abuse email addresses to facilitate incident reporting.
Site observations

Automated reading of the public site. Ratings are indicative.

Business

Company
European Southern Observatory
Description
ESO, European Organisation for Astronomical Research in the Southern Hemisphere, is an intergovernmental science and technology organisation focused on ground-based astronomical observatories and research.
Key services
Astronomical research, Public outreach and education, Provision of observatories and telescopes, Publishing news, images, videos, Technology transfer and industry collaboration
Content quality
excellent
Branding
consistent

Technology

Stack
HTML5, CSS3, JavaScript, jQuery, Slick Carousel, Matomo Analytics, YouTube Iframe API, Fonts.com
Performance
fast
Mobile
good
Accessibility
good
SEO
good

Security

Observed score
90/100
Good practices seen
  • HTTPS enforced
  • CSRF token cookie used
  • Cookie consent mechanism implemented
  • No exposed sensitive data found
  • Use of reCAPTCHA for forms

Analytics and tracking

Services
Matomo
Tracking level
moderate
Privacy practices
good

Advertising

Tracking pixels
Matomo
Marketing tools
Fonts.com
Transparency
excellent

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 no blocking detected.
  2. Comprehensive privacy and cookie policies with consent mechanisms are implemented.
  3. Multiple social media channels linked, indicating active outreach.
  4. No phone numbers or physical addresses explicitly found in the provided content.
  5. WHOIS data is unavailable or malformed, limiting domain registration insights.
  6. Website uses modern web technologies and analytics with privacy considerations.
  7. No security policy or incident response information publicly available.
  8. No vulnerability disclosure or security.txt found.
  9. Content is safe and suitable for general audiences.
  10. Website is well-structured with clear navigation and multilingual support.
Technical notes

Notes

The website is built on a solid technical foundation using standard web technologies and libraries, ensuring compatibility and ease of maintenance. Performance is optimized through CDN usage and asynchronous loading of scripts. The integration of Matomo analytics reflects a commitment to privacy. The site is responsive and accessible, supporting multiple languages and providing rich multimedia content. There is no evidence of legacy or vulnerable libraries. Opportunities exist to modernize security headers and improve documentation of security practices. Overall, the technical infrastructure supports the organization's mission effectively with minimal technical debt.
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

Reviews of this site

Share your experience with eso.org. Every review is verified by email and published after moderation.

Overall rating
Select a rating
4000 characters remaining

We’ll email you to confirm your review and keep your details private.

Community rating

No published reviews yet. Be the first to review eso.org.

Feedback on this report

Rate this report, add an optional comment, and tell us if you want a security specialist to follow up.

Overall report quality
Select a rating
2000 characters remaining

We only use your feedback to improve Guard reports. Contact details are never shared.