DNS Gurus
Cached · just now
88/100 SECURITY SCORE

Detected Technologies

See all in URL Inspect 1
IONOS logo IONOS

Certificate Information

Subject
C=DE, ST=Rheinland-Pfalz, L=Montabaur, O=IONOS SE, CN=webmailer.1und1.de
Issuer
C=DE, O=Deutsche Telekom Security GmbH, UNKNOWN={:asn1_OPENTYPE, <<12, 22, 78, 84, 82, 68, 69, 45, 68, 69, 82, 51, 50, 48, 49, 46, 72, 82, 66, 49, 53, 50, 52, 49>>}, CN=Telekom Security OV RSA CA 26A
Valid From
June 15, 2026
Valid Until
December 29, 2026 148 days
Public Key
RSA 3072 bit Adequate
Signature Algorithm
SHA256-RSA
SHA-256 Fingerprint
C8:C2:C5:DF:AF:85:53:67:86:A7:3A:56:D0:A5:30:DF:1F:45:83:95:41:A5:87:A4:14:A4:FB:BC:76:DA:81:12
Alternative Names
6 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=31556926
Content-Security-Policy
IONOS logo
Good
default-src; frame-src Analyze
Content-Security-Policy-Report-Only
Missing
Not configured Analyze
X-Frame-Options
Good
SAMEORIGIN
X-Content-Type-Options
Good
nosniff
Referrer-Policy
Missing
Not configured
Permissions-Policy
Missing
Not configured
Recommendations
  • • Increase HSTS max-age to at least 1 year and add includeSubDomains
  • • Strengthen CSP by removing 'unsafe-eval'
  • • 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
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