DNS Gurus
Cached · just now
89/100 SECURITY SCORE

Certificate Information

Subject
CN=books.deltaque.io
Issuer
C=US, O=Let's Encrypt, CN=E7
Valid From
November 22, 2025
Valid Until
February 20, 2026 32 days
Public Key
ECDSA 256 bit (P-256) Adequate
Signature Algorithm
ECDSA-SHA384
SHA-256 Fingerprint
ED:95:13:1C:33:ED:76:92:03:18:F5:B9:9B:D6:C6:41:EB:E6:E8:3C:1B:21:FA:FD:88:73:9F:73:00:DA:66:95
Alternative Names
52 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
Excellent
DENY
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
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