Open
Cached
·
just now
75/100
SECURITY SCORE
Detected Technologies
Certificate Information
Subject
CN=gitbook.com
Issuer
C=US, O=Google Trust Services, CN=WE1
Valid From
February 23, 2026
Valid Until
May 24, 2026
89 days
Public Key
ECDSA
256 bit
(P-256)
Adequate
Signature Algorithm
ECDSA-SHA256
SHA-256 Fingerprint
0B:99:CF:95:FA:68:04:81:2D:F8:CC:A7:7B:1C:7B:15:A9:C6:B9:00:20:F1:FD:32:7B:5A:67:0F:30:8D:E1:D4
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
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