SSL Verification Bypassed
The server's SSL certificate could not be verified. The analysis was completed using insecure mode. Data may be less reliable.
Reason:
Hostname Mismatch - certificate is issued for postal.k.io, not for mx.postal.k.io
Open
Cached
·
just now
85/100
SECURITY SCORE
Certificate Information
Subject
CN=postal.k.io
Issuer
C=US, O=Let's Encrypt, CN=R12
Valid From
January 15, 2026
Valid Until
April 15, 2026
73 days
Public Key
RSA
4096 bit
Strong
Signature Algorithm
SHA256-RSA
SHA-256 Fingerprint
32:39:62:65:C5:E6:E2:A3:35:2A:25:09:D4:2D:09:CE:15:1F:9C:D1:11:F9:69:63:20:2D:49:D1:B4:EC:C9:EB
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
Basic
child-src; connect-src; font-src; +4 more
child-src 'self'; connect-src 'self'; font-src 'self' https: data:; img-src 'self' https: data:; object-src 'none'; script-src 'self'; style-src 'self' https: 'unsafe-inline'
X-Frame-Options
Good
sameorigin
X-Content-Type-Options
Good
nosniff
Referrer-Policy
Missing
Not configured
Permissions-Policy
Missing
Not configured
Recommendations
- • Add Strict-Transport-Security header with max-age of at least 1 year
- • Improve CSP by adding more specific directives and removing 'unsafe-inline'
- • 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