BNB Chain will activate the Pasteur hard fork on BNB Smart Chain at 02:30 UTC on Aug. 25, 2026, introducing three proposals that strengthen bridge verification, validator governance and block-processing capacity.
Three Key Proposals
BEP-682 changes how BSC validates blocks used for cross-chain transfers. The network will check validator signatures before accepting information from another chain, ensuring the required voting threshold approved the block. The previous process did not confirm that every validator appeared only once in a submitted validator set. A specially constructed set could theoretically repeat one validator and count its voting power more than once. BEP-682 rejects duplicate entries, making the threshold reflect a genuine validator supermajority.
BEP-695 addresses what happens when validators rotate their consensus keys. After Pasteur, an old consensus key will lose its administrative authority instead of retaining privileges following a rotation. Pending slash evictions will also follow validators to their new keys, preventing a validator from avoiding an outstanding eviction by changing keys. The proposal also blocks blacklisted addresses from using signature-based governance voting to bypass restrictions.
BEP-675 allows builders to submit blocks they have already executed. Validators can check the proposed block against consensus rules, sign and broadcast it, then complete full verification outside the time-sensitive production path.
Performance Gains From Testing
On QANet, an internal test environment designed to reflect BSC's cross-region validator setup, processing within the critical path fell from 125 milliseconds to 15 milliseconds. Average block gas use increased from 46.35 million to 84.15 million against the existing 100 million limit. Throughput rose from 1,237 to 2,324 transactions per second during the same tests.
The block interval remained at 450 milliseconds, while finality lag did not change. BNB Chain cautioned that these figures came from controlled testing rather than live mainnet activity. No comparable mainnet performance increase is confirmed yet.
Mandatory Upgrade Requirements
All BSC mainnet nodes must run client version 1.7.7 before activation. Node operators must also remove EnableBAL from config.toml, otherwise the updated client will fail to start. Several command-line flags are also obsolete or inactive, including journalfile, enablebal and overflowpoolslots.
Regular users and most application developers do not need to migrate funds or change their software. Pasteur has operated on BSC testnet since July 21, and following mainnet activation, operators and developers will monitor whether the capacity gains measured on QANet carry over to live traffic.
What Makes Pasteur Different
Pasteur differs from recent upgrades that primarily reduced block times. Its security changes focus on cross-chain transfers and validator authority, making greater use of existing block capacity while closing validator and bridge security gaps. Builders adopting the new path must operate full nodes because they will produce fully executed blocks, while legacy block bids will remain available.
.jpg)
.jpg)
