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Security report for mozilla.org

Mozilla Corporation · Technology · United States

Low risk. No critical or high findings.

Security score

88/100

Risk levelLow

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

Mozilla Corporation operates as a leading non-profit organization dedicated to promoting an open and privacy-respecting internet. Their flagship product, Firefox, is a widely used browser emphasizing speed, privacy, and user control. The organization also offers complementary services such as Mozilla VPN, Mozilla Monitor, Firefox Relay, and Thunderbird email client, targeting general internet users and privacy-conscious individuals. Mozilla's market position is strong within the technology and open-source communities, supported by a consistent brand and a large user base. Technically, the Mozilla website employs modern web technologies including JavaScript, SVG graphics, and integrates tools like Google Tag Manager and Sentry for analytics and error monitoring. The site is well-optimized for performance, mobile responsiveness, and accessibility, reflecting a mature digital infrastructure. SEO practices are well implemented with comprehensive meta tags and Open Graph data. From a security perspective, the website enforces HTTPS and employs cookie consent mechanisms, demonstrating good privacy compliance aligned with GDPR. However, explicit security headers and a public security.txt file are absent, representing areas for improvement. No vulnerabilities or exposed sensitive data were detected in the HTML content. The WHOIS data is privacy-protected, which is justified given the organization's profile. Overall, Mozilla's website presents a trustworthy, professional, and secure platform with excellent content quality and user experience. Strategic recommendations include enhancing security header implementation, publishing vulnerability disclosure information, and providing clearer incident response contacts to further strengthen security posture and transparency.

Scanned

This is an earlier scan of mozilla.org. View the latest report

NIS2 and GDPR posture

GDPR outside view
83/ 100 · Low
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

No critical or high findings. These medium findings are worth fixing next.

  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.

    • Medium

      Missing X-XSS-Protection header

      Legacy XSS protection (deprecated but still recommended)

      What to do: Add "X-XSS-Protection: 1; mode=block"

    • Medium

      Missing Permissions-Policy header

      Controls browser features and APIs

      What to do: Implement a Permissions-Policy to restrict feature access

      • OWASP Secure Headers: OWASP Secure Headers Project recommends Permissions-Policy: accelerometer=(), autoplay=(), camera=(), cross-origin-isolated=(),…

  2. GDPR outside view

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

    • Medium

      Privacy policy may not be GDPR compliant

      Privacy policy lacks explicit GDPR compliance elements

      What to do: Update privacy policy to explicitly address GDPR requirements and user rights

  3. 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.

    • Medium

      No MTA-STS Policy

      MTA-STS enforces TLS for email delivery

      What to do: Implement MTA-STS to prevent downgrade attacks

  4. 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.

    • Medium

      SSL Certificate Expires Within 90 Days

      SSL certificate expires in 80 days

      What to do: Plan SSL certificate renewal

Keep watching mozilla.org

This scan found 12 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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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
95
Security headers
75
Email security
85
DNS health
90
Network security
100
GDPR outside view
83
Average
88

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 mozilla.org, from OffSeq Breach.

Total records
37,263
Employees
6
Customers
37,204
Third parties
53
Weak passwords
22%

Latest record dated 2026-01-13 · 94 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 mozilla.org.

Select it in the checkout above.

Masked preview

  • –mozilla.org2026-01-13
  • –mozilla.org2025-08-11
  • –support.mozilla.org2025-08-10
  • –support.mozilla.org2025-07-31
  • –support.mozilla.org2025-07-20

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

Mozilla holds a prominent position as a non-profit technology organization focused on internet privacy, open-source software, and user empowerment. Its business model relies on product offerings combined with donations and community support. The organization targets a broad audience including everyday internet users, developers, and privacy advocates. Mozilla's ecosystem includes multiple subsidiaries and initiatives such as Mozilla.ai and Mozilla Ventures, indicating a diversified portfolio. The company benefits from strong brand recognition, consistent messaging, and a global presence. Partnerships and related domains reinforce its market reach and credibility. Growth indicators include active community engagement and expansion into AI and privacy-first advertising. Competitive advantages stem from Mozilla's commitment to privacy, open standards, and transparency, differentiating it from commercial tech giants. Revenue streams are primarily from product-related services and philanthropic contributions. The organization's strategic focus on trustworthy AI and open-source projects positions it well for future technology trends.

Security posture

Mozilla's website demonstrates a mature security posture with mandatory HTTPS usage and privacy-compliant cookie consent mechanisms. The absence of explicit security headers such as Content-Security-Policy and Strict-Transport-Security suggests room for enhancement. No exposed credentials or sensitive information were found, and no vulnerable libraries were detected in the provided HTML content. The use of Sentry for error monitoring indicates proactive incident detection capabilities, though no direct incident response contacts or security policies are publicly visible on the site. Compliance with GDPR is evident through privacy notices and consent banners. The lack of a published security.txt file or explicit vulnerability disclosure policy limits transparency for security researchers. Overall, the security posture is strong but could benefit from formalizing incident response channels and enhancing HTTP security headers to mitigate risks further.

Recommendations

  1. Implement and enforce comprehensive HTTP security headers including Content-Security-Policy, X-Frame-Options, and Strict-Transport-Security.
  2. Publish a security.txt file to provide clear vulnerability disclosure guidelines and contact information.
  3. Add explicit incident response contact details on the website to improve transparency and responsiveness.
  4. Regularly audit and update third-party scripts and libraries to prevent potential vulnerabilities.
  5. Enhance user privacy transparency by detailing data retention policies and cookie usage in accessible formats.
Site observations

Automated reading of the public site. Ratings are indicative.

Business

Company
Mozilla Corporation
Description
Mozilla is a non-profit organization working to put control of the internet back in the hands of the people using it. They offer products such as Firefox browsers, Mozilla VPN, Mozilla Monitor, Firefox Relay, Pocket, MDN Plus, and Thunderbird.
Key services
Firefox browsers, Mozilla VPN, Mozilla Monitor, Firefox Relay, Pocket, MDN Plus, Thunderbird email client
Content quality
excellent
Branding
consistent

Technology

Stack
JavaScript, SVG, Google Tag Manager, Sentry, Mozilla Firefox related technologies
Performance
fast
Mobile
excellent
Accessibility
good
SEO
good

Security

Observed score
90/100
Good practices seen
  • HTTPS enforced
  • Cookie consent mechanism
  • No exposed sensitive data in HTML
  • Use of Sentry for error monitoring

Analytics and tracking

Services
Google Tag Manager
Tracking level
moderate
Privacy practices
good

Advertising

Tracking pixels
Sentry
Transparency
good

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. Strong emphasis on privacy, open-source, and user empowerment.
  3. Comprehensive cookie consent and privacy mechanisms implemented.
  4. No exposed sensitive data or obvious security vulnerabilities found in HTML.
  5. WHOIS data unavailable, likely due to privacy protection, but no suspicious indicators.
  6. Multiple official Mozilla domains linked, reinforcing authenticity.
  7. No adult or questionable content detected; suitable for general audiences.
Technical notes

Notes

The website is built using modern web technologies including JavaScript and SVG for graphics, with integration of Google Tag Manager and Sentry for analytics and error tracking. The site is well-structured with valid HTML and CSS, optimized for fast loading and excellent mobile responsiveness. Accessibility features are present, supporting a broad user base. SEO is well implemented with detailed meta tags and Open Graph data enhancing social media sharing and search engine visibility. No CMS was explicitly detected, suggesting a custom or proprietary platform. Hosting provider details are not evident from the HTML content. Overall, the technical infrastructure is robust, supporting a high-quality user experience and scalable performance.
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. 84/100 −4Low23 findingsView report
  2. 88/100 +8Low20 findingsView report
  3. 80/100Low19 findingsView report
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