SSL/TLS Analysis for kubernetes.io

Analyzed on November 02, 2025 at 19:09 UTC

Security Score
80 / 100

Certificate Information

Subject
CN=kubernetes.io
Issuer
C=US, O=Let's Encrypt, CN=E8
Valid From
October 16, 2025
Valid Until
January 14, 2026 72 days
Public Key
ECDSA 256 bit (P-256) Adequate
Signature Algorithm
ECDSA-SHA384
SHA-256 Fingerprint
41:E2:58:35:F8:04:96:E3:EB:63:33:0C:8F:99:6C:9B:BC:41:67:1E:27:32:26:7D:F1:2C:73:53:34:5E:8D:A9
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
Missing
Not configured
X-Frame-Options
Missing
Not configured
X-Content-Type-Options
Missing
Not configured
Referrer-Policy
Missing
Not configured
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
  • Add X-Frame-Options: DENY or SAMEORIGIN to prevent clickjacking
  • Add X-Content-Type-Options: nosniff
  • 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
Configured (Restricts certificate issuance)
Current Issuer
Authorized (Matches CAA policy)
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

Subject Alternative Names

2 domains