Skip to main content

Security report for slack.com

Slack · Technology · United States

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

Security score

77/100

Risk levelLow

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

Slack is a leading enterprise collaboration platform owned by Salesforce, offering a comprehensive suite of tools for team communication, project management, workflow automation, and AI-powered productivity enhancements. The website reflects a mature, enterprise-grade SaaS business model targeting large organizations and diverse industries. Technically, Slack employs modern web technologies including AWS hosting, React-based frontend, and integrates advanced analytics and consent management tools, ensuring a fast, accessible, and SEO-optimized user experience. Security posture is strong with HTTPS enforcement, multiple security headers, and published compliance certifications such as SOC 2 and ISO 27001. Privacy policies and cookie consent mechanisms are well implemented, supporting GDPR compliance. Overall, Slack's digital presence is professional, trustworthy, and aligned with its market leadership.

Scanned

This is an earlier scan of slack.com. View the latest report

NIS2 and GDPR posture

GDPR outside view
68/ 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 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 slack.com

This scan found 17 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. See sample alerts.

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
62
Security headers
55
Email security
85
DNS health
90
Network security
100
GDPR outside view
68
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

Slack holds a strong market position as a preferred collaboration platform for enterprises, including Fortune 100 companies. Its business model revolves around SaaS subscriptions with tiered pricing plans and enterprise features like key management and compliance tools. The company leverages partnerships with major technology firms such as Salesforce and OpenAI to enhance its AI capabilities and integrations ecosystem. Slack's target customers span multiple industries including technology, finance, healthcare, and manufacturing. The website's rich content, customer testimonials, and solution templates indicate a focus on user adoption and scalability. Slack's strategic emphasis on AI agents and workflow automation positions it well for future growth in digital workplace transformation.

Security posture

Slack demonstrates a mature security posture with enforced HTTPS, comprehensive security headers, and enterprise-grade certifications. The domain registration is consistent and transparent, with no privacy protection masking ownership. The website includes detailed security and privacy documentation, cookie consent management, and vulnerability disclosure information, although a security.txt file is not published. No critical vulnerabilities or exposed sensitive data were detected in the analysis. Incident response contact details are not explicitly provided, which could be improved. Overall, Slack maintains strong security practices appropriate for its enterprise clientele, minimizing risk exposure.

Recommendations

  1. Enable DNSSEC to enhance DNS security and prevent spoofing.
  2. Publish a security.txt file to facilitate responsible vulnerability reporting.
  3. Provide explicit incident response and abuse contact emails on the website.
  4. Increase transparency on data retention policies and user data handling.
  5. Regularly review and audit third-party scripts and integrations for security risks.
Site observations

Automated reading of the public site. Ratings are indicative.

Business

Company
Slack
Description
Slack is where work happens. Bring your people, projects, tools, and AI together on the world’s most beloved work operating system.
Key services
Team messaging, Channels for organization, Slack Connect for external collaboration, Project management tools, Workflow automation, AI-powered agents and Slack AI, Enterprise key management
Content quality
excellent
Branding
consistent

Technology

Stack
JavaScript, React (likely), AWS (Amazon Web Services), Cloudfront CDN, YouTube iframe API, OneTrust (cookie consent), Optimizely (A/B testing), Google Tag Manager
Frameworks
React (inferred from JS and modern SPA structure)
Platforms
Web, Mobile (responsive design)
Performance
fast
Mobile
excellent
Accessibility
good
SEO
good

Security

Observed score
90/100
Good practices seen
  • HTTPS enforced
  • Domain status includes client/server prohibitions
  • Enterprise key management
  • Security and compliance documentation
  • Cookie consent mechanism

Analytics and tracking

Services
Google Tag Manager, Optimizely
Tracking level
moderate
Privacy practices
good

Advertising

Tracking pixels
Optimizely, OneTrust
Marketing tools
Optimizely, OneTrust
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 multimedia.
  2. Strong enterprise focus with extensive product and solution offerings.
  3. Comprehensive security and privacy policies are published.
  4. Use of modern web technologies and performance optimization.
  5. No suspicious or malicious indicators found.
  6. Good integration of consent management and analytics tools.
Technical notes

Notes

Slack's website is built on a modern technology stack leveraging AWS infrastructure and React-based frontend frameworks. The use of CDNs like Cloudfront and optimized media assets contributes to fast loading times and excellent performance. The site is fully responsive with good accessibility features and SEO optimization. Integration of marketing and analytics tools such as Optimizely and Google Tag Manager is done with consent management via OneTrust, reflecting compliance maturity. The technical implementation supports Slack's business goals of scalability, reliability, and user engagement. Opportunities exist to further enhance DNS security and formalize vulnerability disclosure processes.
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. 77/100 −3Low26 findingsView report
  2. 80/100 +7Low24 findingsView report
  3. 73/100Medium22 findingsView report
Reviews of this site

Share your experience with slack.com. 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 slack.com.

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.