papers/lux-achain-attestation/sections/08-security-analysis.tex

\section{Security Analysis}


\subsection{Threat Model}

\textbf{Adversary Capabilities:}
\begin{enumerate}
\item Compromise of individual validator nodes
\item Side-channel attacks on TEE implementations
\item Replay attacks using old attestation quotes
\item Collusion between validators to approve invalid attestations
\end{enumerate}

\textbf{Security Guarantees:}
\begin{itemize}
\item \textbf{Byzantine Fault Tolerance}: 2/3+ honest validators required
\item \textbf{Cryptographic Verification}: All quotes verified against vendor root CAs
\item \textbf{Nonce Protection}: Monotonic nonces prevent replay attacks
\item \textbf{Economic Security}: Slashing penalizes malicious validators
\end{itemize}

\subsection{Quantum Resistance}

A-Chain integrates post-quantum cryptography for long-term security:

\begin{itemize}
\item \textbf{ML-DSA (FIPS 204, formerly CRYSTALS-Dilithium)}: Validator signatures (3,293 bytes)
\item \textbf{ML-KEM}: Encrypted validator communication (1,568-byte ciphertexts)
\item \textbf{Hybrid Mode}: Classical (BLS) + post-quantum (ML-DSA) dual signatures
\item \textbf{Migration Timeline}: Full quantum security by Q4 2027
\end{itemize}