DNS Gurus
Open Cached · just now
79/100 SECURITY SCORE

Certificate Information

Subject
C=AT, ST=Wien, O=Universität Wien, CN=aco.net
Issuer
C=GR, O=Hellenic Academic and Research Institutions CA, CN=GEANT TLS RSA 1
Valid From
October 14, 2025
Valid Until
October 14, 2026 330 days
Public Key
RSA 2048 bit Adequate
Signature Algorithm
SHA256-RSA
SHA-256 Fingerprint
81:8A:69:7B:D8:C2:AB:3E:28:CD:78:5B:48:E7:DD:B4:91:D5:99:CC:30:85:5D:06:DC:1C:F0:86:23:9D:44:E8
Alternative Names
13 domains

Security Configuration

TLS Protocols
TLS 1.2
Forward Secrecy
Limited (Check cipher configuration)
Warnings
  • • TLS 1.3 is not supported (recommended)

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
Missing
Not configured
Referrer-Policy
Missing
Not configured
Permissions-Policy
Present
interest-cohort=()
Recommendations
  • • Increase HSTS max-age to at least 1 year and add includeSubDomains
  • • Add Content-Security-Policy header to prevent XSS attacks
  • • Add X-Content-Type-Options: nosniff
  • • Add Referrer-Policy header (recommended: strict-origin-when-cross-origin)

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