SSL/TLS Analysis for localhost.nu

Analyzed on November 02, 2025 at 18:46 UTC

Security Score
81 / 100

Certificate Information

Subject
CN=localhost.nu
Issuer
C=US, O=Google Trust Services, CN=WE1
Valid From
September 22, 2025
Valid Until
December 21, 2025 48 days
Public Key
ECDSA 256 bit (P-256) Adequate
Signature Algorithm
ECDSA-SHA256
SHA-256 Fingerprint
2D:D2:03:B7:21:DE:F3:DB:05:E4:90:60:54:23:F4:41:FA:A6:13:DE:90:52:31:0D:F0:A1:1C:DF:DE:89:4C:47
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
Missing
Not configured
Content-Security-Policy
Missing
Not configured
X-Frame-Options
Missing
Not configured
X-Content-Type-Options
Good
nosniff
Referrer-Policy
Good
strict-origin-when-cross-origin
Permissions-Policy
Missing
Not configured
Recommendations
  • Add Strict-Transport-Security header with max-age of at least 1 year
  • Add Content-Security-Policy header to prevent XSS attacks
  • Add X-Frame-Options: DENY or SAMEORIGIN to prevent clickjacking
  • 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

Subject Alternative Names

1 domain