DNS Gurus
Cached · just now
89/100 SECURITY SCORE

Certificate Information

Subject
CN=mail.harmonizedx.com
Issuer
C=US, O=Let's Encrypt, CN=R12
Valid From
January 07, 2026
Valid Until
April 07, 2026 64 days
Public Key
RSA 2048 bit Adequate
Signature Algorithm
SHA256-RSA
SHA-256 Fingerprint
00:1E:D2:7D:9D:D3:0A:E6:DF:67:A6:A3:8E:9A:B0:33:CC:B8:CE:76:42:AF:AD:45:5C:FA:40:42:79:90:0A:B7
Alternative Names
25 domains

Security Configuration

TLS Protocols
TLS 1.2 TLS 1.3
Forward Secrecy
Supported (Modern clients use PFS)

HTTP Security Headers

Status
Strict-Transport-Security
Excellent
max-age=64072000; includeSubDomains; preload
Content-Security-Policy
Missing
Not configured
X-Frame-Options
Good
SAMEORIGIN
X-Content-Type-Options
Good
nosniff
Referrer-Policy
Missing
Not configured
Permissions-Policy
Missing
Not configured
Recommendations
  • • Add Content-Security-Policy header to prevent XSS attacks
  • • 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
Configured (Restricts certificate issuance)
Current Issuer
Authorized (Matches CAA policy)
Authorized CAs
letsencrypt.org pki.goog
Recommendations
  • • Consider using critical flag (flags=128) for stricter CAA enforcement
  • • Consider adding 'iodef' records to receive notifications about unauthorized certificate issuance attempts
  • • Consider adding 'issuewild' records to control wildcard certificate issuance