BNB Smart Chain Deploys Pasteur Hard Fork to Enhance Bridge Security and Transaction Capacity

Pasteur Hard Fork Activates for Enhanced Security

BNB Smart Chain activated its Pasteur hard fork on Tuesday, implementing critical security improvements across the network’s bridge, staking, and governance infrastructure. According to BNB Chain, the upgrade addresses vulnerabilities in bridge verification and validator authorization while preserving the network’s established 450-millisecond block time. The upgrade combines three separate BNB Evolution Proposals, each targeting specific operational and security concerns that have accumulated across the chain’s architecture.

Three Proposals Strengthen Network Architecture

BEP-682 eliminates a verification vulnerability by rejecting duplicate validator entries during cross-chain light-block verification—preventing individual validators from being counted multiple times when approving bridge transactions. BEP-695 reinforces controls governing validator key rotation, slashing mechanisms, and governance voting eligibility, removing authority from outdated validator keys while blocking restricted addresses from participation in voting procedures. BEP-675 introduces a structural change to the block-building workflow, fundamentally altering how specialist builders interact with validators during block proposal and execution.

The previous block construction process created inefficiencies: builders would execute transactions and propose a block, then validators would redundantly execute the same transactions again before signing and broadcasting. This double-execution consumed precious time within BSC’s tight millisecond-scale block window, often leaving blocks underfilled with transactions. Under the new BEP-675 route, builders submit pre-executed blocks to validators, who check them against consensus rules, sign and broadcast them, then verify full execution afterward. The system maintains backward compatibility, allowing builders to continue using the previous validation path if preferred.

Testing Reveals Substantial Throughput Potential

BNB Chain conducted testing on QANet, an internal environment mirroring BSC’s geographically distributed validator infrastructure. Results demonstrated significant efficiency improvements: the new block-building route achieved approximately 88 percent higher throughput, increasing from 1,237 to 2,324 transactions per second. Gas consumption per block rose from 46.35 million to 84.15 million units, while the block interval and 100-million-gas-limit remained unchanged. BNB Chain emphasized that these measurements came from controlled test workloads and should not be interpreted as live mainnet performance expectations.

Pasteur represents the latest evolution in BSC’s performance enhancement trajectory. The Maxwell hard fork previously reduced average block times from 1.5 seconds to approximately 0.8 seconds in June 2025, with the subsequent Fermi upgrade further compressing block times to the current 450-millisecond standard. Each successive upgrade has pushed boundaries on both security and throughput.

The security improvements matter particularly in the current environment—bridge vulnerabilities have proven costly across the crypto industry. Higher transaction capacity without sacrificing security addresses a fundamental constraint that has limited blockchains’ practical utility. For the broader ecosystem, upgrades like Pasteur demonstrate how interconnected chains continue optimizing their infrastructure, potentially enabling smoother cross-chain interactions and reduced settlement friction across the industry.

Source: BNB Chain, via Cointelegraph. Not financial advice.