wFabricSecurity adds TTL and SHA-256 hashing to block blockchain replay attacks

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An open-source Python library called wFabricSecurity has introduced automatic Time-To-Live (TTL) validation and SHA-256 payload hashing to protect Hyperledger Fabric blockchain networks. The tool is designed to prevent replay attacks, where intercepted valid transactions are maliciously resubmitted, a threat that can cause significant financial damage in sectors like finance and supply chain. Each message is assigned a unique ID and timestamp nonce, causing it to expire if not processed within a defined time window, such as 60 seconds. The library also detects bit-level data corruption during network transmission by verifying a cryptographic hash of the payload before acceptance. Compatible with Python 3.10 and above, wFabricSecurity is available on both GitHub and PyPI as part of an ongoing open-source engineering series.

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