Open Cached · just now
87/100 SECURITY SCORE

Certificate Information

Subject
CN=post.knipp.de
Issuer
C=US, O=Let's Encrypt, CN=R13
Valid From
October 29, 2025
Valid Until
January 27, 2026 82 days
Public Key
RSA 4096 bit Strong
Signature Algorithm
SHA256-RSA
SHA-256 Fingerprint
6D:84:CA:51:1A:57:56:0B:04:FB:9A:A3:AF:8B:7F:F3:6D:DF:0C:C5:74:8B:5B:49:79:BB:FD:44:9F:F7:DC:9D
Alternative Names

Security Configuration

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

HTTP Security Headers

Status
Strict-Transport-Security
Present
max-age=15768000;
Content-Security-Policy
Missing
Not configured
X-Frame-Options
Good
SAMEORIGIN
X-Content-Type-Options
Good
nosniff
Referrer-Policy
Good
strict-origin
Permissions-Policy
Missing
Not configured
Recommendations
  • Increase HSTS max-age to at least 1 year and add includeSubDomains
  • Add Content-Security-Policy header to prevent XSS attacks
  • 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