DNS Gurus
Cached · just now
87/100 SECURITY SCORE

Certificate Information

Subject
C=CZ, L=Praha 6, O=CESNET, CN=doku.cesnet.cz
Issuer
C=GR, O=Hellenic Academic and Research Institutions CA, CN=GEANT TLS RSA 1
Valid From
March 23, 2026
Valid Until
October 08, 2026 74 days
Public Key
RSA 2048 bit Adequate
Signature Algorithm
SHA256-RSA
SHA-256 Fingerprint
1D:51:6F:4B:9B:DE:43:DB:90:D3:8A:F4:C2:A0:C9:19:E3:9B:7D:60:ED:B1:DF:AB:55:38:4E:91:05:B8:8C:BB
Alternative Names
51 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
Good
max-age=31536000;includeSubDomains
Content-Security-Policy
Missing
Not configured Analyze
Content-Security-Policy-Report-Only
Missing
Not configured Analyze
X-Frame-Options
Good
SAMEORIGIN
X-Content-Type-Options
Good
nosniff
Referrer-Policy
Good
no-referrer-when-downgrade
Permissions-Policy
Missing
Not configured
Recommendations
  • • Consider adding 'preload' to HSTS for maximum security
  • • Add Content-Security-Policy header to prevent XSS attacks
  • • Consider adding Permissions-Policy to control browser features

CAA Records (Certificate Authority Authorization)

CAA Records
Configured (Restricts certificate issuance)
Current Issuer
Not Authorized (Potential misconfiguration)
Authorized CAs
sectigo.com harica.gr letsencrypt.org
CAA Issues
  • • CRITICAL: Current certificate issuer 'C=GR, O=Hellenic Academic and Research Institutions CA, CN=GEANT TLS RSA 1' is NOT authorized by CAA records. Authorized CAs: sectigo.com, harica.gr, 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