DNS Gurus
Cached · just now
80/100 SECURITY SCORE

Detected Technologies

See all in URL Inspect 1
Let's Encrypt logo Let's Encrypt

Certificate Information

Subject
CN=a4a.de
Issuer
C=US, O=Let's Encrypt, CN=R13
Valid From
March 28, 2026
Valid Until
June 26, 2026 61 days
Public Key
RSA 2048 bit Adequate
Signature Algorithm
SHA256-RSA
SHA-256 Fingerprint
2D:E8:FD:34:60:FD:12:CC:DB:BA:E4:02:3F:F4:8D:20:A5:A2:20:77:DF:C4:E6:70:DA:2B:4E:61:1B:EF:86:05
Alternative Names
2 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
Present
max-age=31536000
Content-Security-Policy
Missing
Not configured Analyze
Content-Security-Policy-Report-Only
Missing
Not configured Analyze
X-Frame-Options
Missing
Not configured
X-Content-Type-Options
Missing
Not configured
Referrer-Policy
Missing
Not configured
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
  • • Add X-Frame-Options: DENY or SAMEORIGIN to prevent clickjacking
  • • 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
Configured (Restricts certificate issuance)
Current Issuer
Authorized (Matches CAA policy)
Authorized CAs
letsencrypt.org
Incident Reporting
Recommendations
  • • Consider adding 'issuewild' records to control wildcard certificate issuance

Subject Alternative Names

2 domains
a4a.de www.a4a.de