Cached · just now
91/100 SECURITY SCORE

Certificate Information

Subject
CN=mainlib.org
Issuer
C=US, O=Let's Encrypt, CN=R12
Valid From
December 07, 2025
Valid Until
March 07, 2026 52 days
Public Key
RSA 2048 bit Adequate
Signature Algorithm
SHA256-RSA
SHA-256 Fingerprint
E3:9D:D5:4B:91:B4:54:2F:9A:28:04:74:B9:B9:C6:78:C1:00:4E:41:A5:77:38:5C:E7:66:B3:A6:11:3B:FC:71
Alternative Names

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
Basic
default-src; script-src; connect-src; +5 more
X-Frame-Options
Good
SAMEORIGIN
X-Content-Type-Options
Good
nosniff
Referrer-Policy
Good
strict-origin-when-cross-origin
Permissions-Policy
Present
*
Recommendations
  • Increase HSTS max-age to at least 1 year and add includeSubDomains
  • Improve CSP by adding more specific directives and removing 'unsafe-inline'

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