Open
Cached
·
just now
91/100
SECURITY SCORE
Detected Technologies
Certificate Information
Subject
CN=proton.me
Issuer
C=US, O=Let's Encrypt, CN=R13
Valid From
January 25, 2026
Valid Until
April 25, 2026
30 days
Public Key
RSA
4096 bit
Strong
Signature Algorithm
SHA256-RSA
SHA-256 Fingerprint
7C:A1:E5:55:03:45:18:EB:46:21:EF:E4:D8:22:18:63:5C:AC:05:30:33:71:4E:7A:CC:5F:D9:A7:BA:61:F0:4A
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
X-Frame-Options
Missing
Not configured
X-Content-Type-Options
Good
nosniff
Referrer-Policy
Good
strict-origin-when-cross-origin
Permissions-Policy
Missing
Not configured
Recommendations
- • Strengthen CSP by removing 'unsafe-eval'
- • 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
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