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Security report for userstack.com

userstack · Technology · N/a

Medium risk. 3 critical or high findings in Security headers, GDPR outside view and 1 other check.

Security score

73/100

Risk levelMedium

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

userstack is a technology company specializing in providing a real-time User-Agent lookup and device detection API service. Established in 2011, it offers scalable and accurate user-agent parsing solutions trusted by thousands of customers worldwide, including major brands such as Amazon, Apple, and Zendesk. The company operates a freemium business model with free API access and tiered paid plans, targeting developers and businesses requiring device and browser detection capabilities. The website demonstrates strong branding consistency and professional content quality, with extensive code examples and clear calls to action.

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

3 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 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 SSL Key Length

      SSL certificate uses 256-bit key, which is considered weak

      What to do: Use at least 2048-bit RSA or 256-bit ECC key

      • CWE-326
      • OWASP A04:2025
      • Mozilla TLS: Mozilla Server Side TLS 6.0 intermediate: rsa_key_size 2048

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

Keep watching userstack.com

This scan found 19 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

€39.90one-time

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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
75
Security headers
45
Email security
70
DNS health
75
Network security
100
GDPR outside view
73
Average
73

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

userstack holds a solid market position as a niche API provider within the developer tools sector. Its competitive advantages include a highly accurate and constantly updated user-agent database, seamless integration via a simple JSON REST API, and a scalable cloud infrastructure. Revenue streams are primarily subscription-based, with a free tier to attract new users. The company benefits from a partnership or parent relationship with apilayer, which provides a broader API marketplace and affiliate program. The target customer segments are developers, SaaS companies, and enterprises needing device detection. Growth indicators include a mature domain age and presence of major client logos. Strategic partnerships with apilayer enhance its ecosystem and market reach.

Security posture

The website enforces HTTPS and uses Cloudflare for DNS and CDN services, providing a strong baseline for security. Security best practices observed include the use of Google reCAPTCHA on forms to prevent abuse and domain status flags to prevent unauthorized domain changes. However, DNSSEC is not enabled, representing a minor security gap. No explicit security policy or incident response information is published, and no vulnerability disclosure or security.txt file is found, which could be improved to enhance transparency and trust. No vulnerabilities or exposed sensitive data were detected in the HTML content. Overall, the security posture is good but could benefit from more explicit security documentation and DNSSEC implementation.

Recommendations

  1. Enable DNSSEC on the domain to improve DNS security and prevent spoofing.
  2. Publish a dedicated security policy page outlining security practices and incident response procedures.
  3. Provide clear incident response contact channels such as security@ or abuse@ email addresses.
  4. Implement and publish a vulnerability disclosure policy or security.txt file to encourage responsible reporting.
  5. Enhance privacy compliance disclosures by explicitly linking privacy and cookie policies on all pages.
Site observations

Automated reading of the public site. Ratings are indicative.

Business

Company
userstack
Description
userstack provides a lightweight User-Agent lookup JSON and XML API for real-time device, browser, and OS detection.
Key services
User-Agent lookup API, Device detection, Browser detection, Operating system detection
Content quality
excellent
Branding
consistent

Technology

Stack
HTML5, CSS3, JavaScript, Google Tag Manager, Stripe (payment processing), Cloudflare (DNS and CDN), jQuery, Google reCAPTCHA
Performance
fast
Mobile
excellent
Accessibility
good
SEO
good

Security

Observed score
85/100
Good practices seen
  • HTTPS enforced
  • Use of Google reCAPTCHA on forms
  • No exposed sensitive data in HTML
  • Domain status includes clientDeleteProhibited etc. to prevent unauthorized changes

Analytics and tracking

Services
Google Analytics (via Google Tag Manager)
Tracking level
moderate
Privacy practices
good

Advertising

Ad networks
Reddit Ads
Tracking pixels
Cookie Script
Marketing tools
FirstPromoter
Transparency
good

Site quality

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

Key observations

  1. Website offers a specialized API service for user-agent parsing and device detection.
  2. Content is rich with code examples in multiple programming languages.
  3. Strong branding and trust signals with major client logos and positive ratings.
  4. Use of modern web technologies and security best practices.
  5. No direct contact emails or phone numbers found; contact is via web form.
  6. No explicit security or incident response policies published.
  7. No vulnerability disclosure or security.txt found.
  8. No privacy or cookie policies explicitly linked in the provided HTML but inferred from domain structure and typical site layout.
Technical notes

Notes

The website is built with modern web technologies including HTML5, CSS3, and JavaScript, leveraging Google Tag Manager for analytics and Stripe for payment processing. It uses Cloudflare for DNS and CDN, enhancing performance and security. The site is mobile-optimized with responsive design and good accessibility features. SEO is well addressed with proper meta tags and structured content. The presence of multiple code examples in various programming languages demonstrates technical maturity and developer focus. No CMS was detected, indicating a custom or proprietary platform. Performance is fast, and the site shows no signs of technical debt or outdated libraries. Opportunities exist to improve security documentation and DNS configuration.
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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