TLDR:
- BNB Chain’s Pasteur hardfork activates on BSC Smart Chain mainnet at 02:30 UTC on August 25, 2026
- BEP-682 stops validators from counting duplicate signatures during cross-chain verification
- Testnet benchmarks showed throughput climbing from 1,237 to 2,324 TPS at the same block time
- Node operators must upgrade to client v1.7.7 before the mainnet activation window opens on August 25
BNB Chain will activate its Pasteur hardfork on BNB Smart Chain mainnet at 02:30 UTC on August 25. The upgrade closes two validator loopholes and lets blocks carry more transactions at the same 450ms block time.
Node operators must run client v1.7.7 before the activation window opens. BNB Chain confirmed the rollout in an announcement covering three linked proposals grouped under BEP-673.
What The Pasteur Hardfork Changes On BSC
BSC verifies cross-chain transfers by checking that enough validators on the sending side signed off. Before Pasteur, a crafted validator set could list the same signer more than once and still clear that threshold.
BEP-682 closes that gap. The precompile handling verification now rejects any signature set containing duplicate validators, so each validator only counts once.
BEP-695 targets validator key rotation instead. A rotated key immediately loses admin authority, where it previously kept privileges it should have given up.
Pending slash evictions now follow a validator through key rotation too. Blacklisted addresses are also blocked on signature-based governance votes. That closes a path around a check already applied to direct voting.
Pasteur has been live on BSC testnet since July 21. The three proposals ship together, following earlier upgrades that focused purely on speed rather than security.
Throughput Gains And What Comes Next
BEP-675 tackles a separate bottleneck in how blocks get built. Builders and validators currently execute every transaction twice, once each, and that repeat work eats into the 450ms block window.
The proposal lets a validator sign a block the builder already executed, then verify it afterward. Throughput on an internal testnet called QANet rose from 1,237 to 2,324 TPS. That held at the same block time and gas limit, according to BNB Chain.
Average block gas used climbed from 46.35 million to 84.15 million of the 100 million available. BNB Chain noted these figures come from a controlled testnet workload, not confirmed mainnet performance.
BEP-675 does not require its own hardfork. The feature stays gated behind Pasteur and gets switched on separately through RPC, giving builders time to integrate first.
Node operators need v1.7.7 installed before the activation window. EnableBAL must be removed from config.toml first, or the node will not start.
Several CLI flags are also gone in this release, including journalfile and multidatabase, along with older transaction pool settings.
Builders seeking the BEP-675 path must run a fullnode rather than a fastnode. That’s because the builder now has to produce a fully executed block. Everyone else, including regular BSC users, has nothing to do and faces no migration.
BNB Chain lists BEP-675 under its broader capacity push for the second half of 2026, aimed at doubling mainnet throughput. Whether the QANet gains hold once Pasteur reaches mainnet scale remains an open question.
