SSL/TLS Best Practices

TLS

• Ciphersuite negotiation
• Master Secret generation (FS) 

• Authentication
• Confidentiality
• Integrity

Versions

• SSL 2.0 (MD5, MITM Downgrade)
• SSL 3.0 (POODLE)
• TLS 1.0 (BEAST)
• TLS 1.1 (CRIME, BREACH)
• TLS 1.2

Ciphersuite

• TLS_RSA_WITH_AES_128_CBC_SHA
  • RSA - Key negotiation
  • AES128 CBC - symmetric cipher
  • SHA1 - HMAC

IIS

• Defaults not optimal (SSLLabs)
• Changed via registry keys
• 3rd party tools (IISCrypto)

HSTS

• Always use HTTPS
• Server redirects (first request)
• Headers and Preloaded lists

HTTP/2

• Requires TLS 1.2 No Compression
• Opportunistic encryption
• All implementations so far over TLS