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Security report for zalo.vn

Zalo Group · Technology · Vietnam

Low risk. 3 critical or high findings in Security headers and GDPR outside view.

Security score

77/100

Risk levelLow

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

Zalo Group operates the Zalo PC platform, a leading Vietnamese messaging application offering desktop clients for Windows, Mac OS, and web access. The platform targets general users and business teams, providing features such as large file transfers, group chat optimization, and synchronization with mobile devices. The website is professionally designed, consistent in branding, and provides clear navigation and relevant content in Vietnamese. The business model includes free software downloads and additional services for enterprises such as Official Accounts and developer APIs. Technically, the site uses modern JavaScript libraries like jQuery and Bootstrap, integrates Google Analytics and adtima for marketing and tracking, and supports multiple platforms. Performance and mobile optimization are good, though accessibility features are basic. Security posture is moderate with HTTPS implied but lacks DNSSEC and explicit security headers. Privacy compliance is basic with cookie consent implemented but no detailed privacy or security policies visible on the main page. WHOIS data shows privacy protection but domain age and registrar are consistent with a legitimate business. Overall, the site is trustworthy and professional but could improve security and compliance transparency.

Scanned

NIS2 and GDPR posture

GDPR outside view
65/ 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 X-Frame-Options header

      Prevents clickjacking attacks

      What to do: Add "X-Frame-Options: DENY" or "X-Frame-Options: SAMEORIGIN"

  2. GDPR outside view

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

    • 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

      What to do: Document all third-party data sharing in your privacy policy

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

Keep watching zalo.vn

This scan found 18 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

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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
100
Security headers
45
Email security
75
DNS health
75
Network security
100
GDPR outside view
65
Average
77

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

Zalo Group holds a strong market position in Vietnam as a top messaging platform with a large user base. Its competitive advantage lies in localized features, integration across devices, and business services like Official Accounts and developer APIs. The business model relies on free user software with monetization through business services and advertising. The target customers include individual users and enterprises seeking communication tools. The company demonstrates growth through platform expansion and ecosystem partnerships. The website ecosystem includes related domains for business accounts, developer resources, and support, indicating a mature partnership and service network. Strategic observations suggest focusing on enhancing security transparency and expanding compliance documentation to strengthen trust further.

Security posture

The website demonstrates a moderate security maturity level. HTTPS is used, and cookie consent is implemented, indicating awareness of privacy requirements. However, the absence of DNSSEC and security headers such as Content Security Policy or HSTS reduces the security posture. No explicit security policies or incident response contacts are published, which limits transparency and readiness. The use of third-party analytics and marketing scripts introduces moderate tracking but is managed with consent mechanisms. No vulnerabilities or exposed sensitive data were detected in the content. Compliance with GDPR is partial, with privacy policies present but not comprehensive. Overall, the security culture appears functional but could benefit from formalized policies and enhanced technical controls.

Recommendations

  1. Enable DNSSEC on the domain to improve DNS security and trust.
  2. Implement and enforce security headers such as Content Security Policy, HSTS, X-Frame-Options, and X-Content-Type-Options.
  3. Publish a dedicated security policy and incident response contact information to improve transparency and readiness.
  4. Enhance accessibility features to meet higher standards and improve user experience for all users.
  5. Expand privacy compliance documentation to explicitly address GDPR and other relevant regulations.
Site observations

Automated reading of the public site. Ratings are indicative.

Business

Company
Zalo Group
Description
Ứng dụng Zalo PC cho máy tính với các tính năng như gửi file 1GB, chụp màn hình, phân loại nhóm, đồng bộ tin nhắn với điện thoại, tối ưu cho chat nhóm và trao đổi công việc.
Key services
Instant messaging, File transfer up to 1GB, Group chat optimization, Official Account platform for businesses, Developer API access
Content quality
good
Branding
consistent

Technology

Stack
jQuery, Bootstrap, Swiper, Google Analytics, adtima conversion tracking, session-sdk.min.js
Platforms
Windows, Mac OS, Web
Performance
moderate
Mobile
good
Accessibility
basic
SEO
good

Security

Observed score
65/100
Good practices seen
  • Use of HTTPS (implied by domain and Google Analytics usage)
  • Cookie consent popup with accept/deny options

Analytics and tracking

Services
Google Analytics, adtima
Tracking level
moderate
Privacy practices
basic

Advertising

Ad networks
adtima
Tracking pixels
adtima
Marketing tools
adtima conversion tracking
Transparency
basic

Site quality

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

Key observations

  1. Website is fully accessible with no blocking or WAF challenges.
  2. Content is professional and targeted at Vietnamese users.
  3. No direct contact emails or phone numbers found on the page.
  4. Cookie consent mechanism is implemented with accept and deny options.
  5. No explicit security policy or incident response contacts published.
  6. Use of multiple external analytics and marketing scripts.
  7. No DNSSEC enabled on domain.
  8. No visible security headers in HTML content.
  9. WHOIS data is privacy protected but domain age and registrar are legitimate.
Technical notes

Notes

The website uses a modern technology stack including jQuery, Bootstrap, and Swiper for UI components, and integrates Google Analytics and adtima for analytics and marketing. The platform supports Windows, Mac OS, and web clients, indicating a multi-platform approach. Performance is moderate with asynchronous script loading and responsive design. The site lacks visible CMS identification and hosting provider details. Technical debt appears low, but security technical controls could be improved. The site is well-structured with proper meta tags and SEO optimization. Opportunities exist to modernize security configurations and enhance accessibility compliance to reduce technical risks.
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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