DNS Gurus
Open Cached · just now
76/100 SECURITY SCORE

Certificate Information

Subject
CN=mail.on-us.com
Issuer
C=US, O=Let's Encrypt, CN=R13
Valid From
November 03, 2025
Valid Until
February 01, 2026 65 days
Public Key
RSA 3072 bit Adequate
Signature Algorithm
SHA256-RSA
SHA-256 Fingerprint
A7:7C:96:4F:CB:66:A0:28:2A:CD:6D:18:59:19:D3:A1:83:A8:F8:1B:B0:63:9E:17:12:AC:55:4E:DC:7F:FB:4B
Alternative Names
4 domains

Security Configuration

TLS Protocols
TLS 1.2
Forward Secrecy
Limited (Check cipher configuration)
Warnings
  • • TLS 1.3 is not supported (recommended)

HTTP Security Headers

Status
Strict-Transport-Security
Missing
Not configured
Content-Security-Policy
Missing
Not configured
X-Frame-Options
Good
SAMEORIGIN
X-Content-Type-Options
Missing
Not configured
Referrer-Policy
Missing
Not configured
Permissions-Policy
Missing
Not configured
Recommendations
  • • Add Strict-Transport-Security header with max-age of at least 1 year
  • • Add Content-Security-Policy header to prevent XSS attacks
  • • Add X-Content-Type-Options: nosniff
  • • Add Referrer-Policy header (recommended: strict-origin-when-cross-origin)
  • • Consider adding Permissions-Policy to control browser features

CAA Records (Certificate Authority Authorization)

CAA Records
Not Configured (Any CA can issue certificates)
CAA Issues
  • • No CAA records configured - any CA can issue certificates
Recommendations
  • • Implement CAA records to restrict which CAs can issue certificates for your domain
  • • This adds an extra layer of security against unauthorized certificate issuance
  • • Example: Add CAA record 'example.com. CAA 0 issue "letsencrypt.org"'
  • • Consider adding 'iodef' record to receive security incident reports

Subject Alternative Names

4 domains
autodiscover.mojo-domo.com mail.mojo-domo.com

Other domains in certificate

autodiscover.on-us.com mail.on-us.com