SSL Certificate Analysis for localhost.delft.rent - Security Grade & TLS Configuration

Open Cached · just now

76/100 SECURITY SCORE

Certificate Information

Subject

CN=delft.rent

Issuer

C=US, O=Let's Encrypt, CN=R13

Valid From

February 05, 2026

Valid Until

May 06, 2026 83 days

Public Key

RSA 4096 bit Strong

Signature Algorithm

SHA256-RSA

SHA-256 Fingerprint

B8:42:58:20:5B:65:B8:24:52:E2:04:37:D9:0D:4F:3B:8A:C1:A7:11:49:37:20:97:A7:93:EC:28:C6:10:3E:17

Alternative Names

90 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

Missing

Not configured

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

• 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
• 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

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