Open
Cached
·
just now
95/100
SECURITY SCORE
Certificate Information
Subject
CN=*.fastmail.com
Issuer
C=US, O=Let's Encrypt, CN=R13
Valid From
October 03, 2025
Valid Until
January 01, 2026
57 days
Public Key
RSA
2048 bit
Adequate
Signature Algorithm
SHA256-RSA
SHA-256 Fingerprint
92:08:76:83:DD:FC:6B:93:74:31:F0:39:45:01:A6:46:8A:64:27:17:0A:A2:26:33:CA:54:BC:52:64:0D:EB:7D
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
Excellent
max-age=31536000; includeSubDomains; preload
Content-Security-Policy
Good
default-src; connect-src; img-src; +11 more
X-Frame-Options
Excellent
DENY
X-Content-Type-Options
Good
nosniff
Referrer-Policy
Present
never,no-referrer,same-origin
Permissions-Policy
Present
accelerometer=(), ambient-light-sensor=(), camera=(), document-domain=(), encrypted-media=(), gyroscope=(), magnetometer=(), microphone=(), midi=(), navigation-override=(), sync-xhr=(), usb=(), xr-spatial-tracking=()
Recommendations
- • Strengthen CSP by removing 'unsafe-eval'
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