Chapter 1
Cloud Architecture
Course: Comptia Cloud Cv0 004
Subject: Comptia Cloud Cv0004
Chapter: Troubleshooting
1. Cipher Suite Deprecations
Issue:
The use of deprecated or insecure cryptographic cipher suites poses significant risks to data confidentiality and integrity. Modern systems may disable older cipher suites in line with updated security standards (e.g., PCI-DSS, NIST, or browser policies), leading to compatibility and connectivity issues.
Common Deprecated Ciphers:
- RC4 – Known for biases in keystream output.
- DES / 3DES – Weak due to small key sizes (56-bit for DES, 112-bit for 3DES).
- MD5-based HMACs – Vulnerable to collision attacks.
- Null ciphers – Provide no encryption, sometimes used in debugging.
- Export-grade ciphers (e.g., EXP-RC4) – Originally designed for export restrictions, now obsolete.
Symptoms:
- TLS/SSL handshake failures due to client-server cipher suite mismatches.
- Browser warnings such as:
“Your connection is not private.”