Open
Cached
·
just now
89/100
SECURITY SCORE
Certificate Information
Subject
CN=gitbook.io
Issuer
C=US, O=Google Trust Services, CN=WE1
Valid From
September 25, 2025
Valid Until
December 24, 2025
32 days
Public Key
ECDSA
256 bit
(P-256)
Adequate
Signature Algorithm
ECDSA-SHA256
SHA-256 Fingerprint
8C:B1:5D:2E:76:0E:C4:B3:2B:12:2E:B4:55:9E:3A:08:77:5D:26:46:7C:44:1B:BC:17:C3:A4:BD:1B:56:E6:E2
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
Present
max-age=31536000
Content-Security-Policy
Basic
default-src; script-src; style-src; +8 more
default-src 'self' *; script-src 'self' 'unsafe-inline' 'unsafe-eval' *; style-src 'self' 'unsafe-inline' blob: *; img-src * 'self' blob: data:; connect-src *; font-src *; frame-src *; object-src 'none'; base-uri 'self' https://static-2c.gitbook.com; form-action 'self' https://static-2c.gitbook.com *; frame-ancestors https: ;
X-Frame-Options
Missing
Not configured
X-Content-Type-Options
Good
nosniff
Referrer-Policy
Good
no-referrer-when-downgrade
Permissions-Policy
Missing
Not configured
Recommendations
- • Increase HSTS max-age to at least 1 year and add includeSubDomains
- • Improve CSP by adding more specific directives and removing 'unsafe-inline'
- • 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
Configured
(Restricts certificate issuance)
Current Issuer
Authorized
(Matches CAA policy)
Authorized CAs
Recommendations
- • Consider using critical flag (flags=128) for stricter CAA enforcement
- • Consider adding 'iodef' records to receive notifications about unauthorized certificate issuance attempts
- • Consider adding 'issuewild' records to control wildcard certificate issuance