Recent failures of production systems have highlighted the importance of tolerating faults beyond crashes. The industry has so far addressed this problem by hardening crash-tolerant systems with ad hoc error detection checks, potentially overlooking critical fault scenarios. The authors propose a generic and principled hardening technique for Arbitrary State Corruption (ASC) faults, which specifically model the effects of realistic data corruptions on distributed processes. Hardening does not require the use of trusted components or the replication of the process over multiple physical servers. They implemented a wrapper library to transparently harden distributed processes.