Infrastructure as a Security Frontier: Winning a 150 XTZ Bounty in the Tezos Ecosystem

Introduction In the world of Web3, security is often synonymous with smart contract auditing. However, the most robust protocol is only as secure as the infrastructure it runs on. Recently, I had the opportunity to contribute to the Tezos ecosystem by hardening its infrastructure components, specifically for the Tez Capital initiative. This journey resulted in a 150 XTZ bounty and some valuable insights into hardware-level security for blockchain validators. Radxa Rock 5B Kernel Optimization The first challenge involved the Radxa Rock 5B, a powerful ARM-based SBC often used for running decentralized nodes. My task was to optimize the kernel configuration to ensure maximum stability and security for validator operations. This included: Fine-tuning kernel parameters for high-load network environments. Stripping unnecessary modules to reduce the attack surface. Ensuring seamless compatibility with the Tezos node requirements. Hardening TezSign (Air-gapped Signing) The second part of the m