DNS Gurus
Cached · just now
89/100 SECURITY SCORE

Certificate Information

Subject
CN=status.altmetric.com
Issuer
C=US, O=Let's Encrypt, CN=R13
Valid From
December 31, 2025
Valid Until
March 31, 2026 79 days
Public Key
RSA 2048 bit Adequate
Signature Algorithm
SHA256-RSA
SHA-256 Fingerprint
D5:86:3B:D6:09:1B:9A:6E:0D:A8:7D:80:24:A1:33:A1:56:96:00:F8:B7:AA:D2:3F:D7:9E:E6:56:23:B5:F4:95
Alternative Names
33 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=259200
Content-Security-Policy
Missing
Not configured
X-Frame-Options
Good
SAMEORIGIN
X-Content-Type-Options
Good
nosniff
Referrer-Policy
Good
strict-origin-when-cross-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
Configured (Restricts certificate issuance)
Current Issuer
Authorized (Matches CAA policy)
Authorized CAs
letsencrypt.org globalsign.com
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