BNB Chain has scheduled its Pasteur hard fork for August 25, 2025, at 02:30 UTC, requiring every node operator on the network to upgrade to client version 1.7.7. The upgrade bundles cross-chain security fixes, staking governance hardening, and system contract changes designed to push the network closer to doubling its mainnet throughput. The network has instructed operators to complete these updates to prevent their nodes from falling out of sync during the upgrade process. BSC's Chapel testnet activated a version of the Pasteur hardfork on July 21, 2025, running client version v1.7.6, giving developers roughly five weeks of live data before the mainnet activation.
The Pasteur upgrade includes BEP-682, which targets a specific vulnerability in CometBFT light client validation. Currently, it's theoretically possible for duplicate validators to slip through the verification process used by cross-chain bridges. BEP-682 closes this gap by explicitly rejecting duplicate bridge validators, ensuring cross-chain transfers require proper approval from the required number of separate validators. This enhancement comes amid increased attention to cross-chain security following recent attacks, including a $9 million loss of NIGHT tokens from a Cardano-to-BNB Chain bridge in July.
BEP-695 introduces significant changes to validator key management and governance participation. The proposal ensures that old validator keys lose management rights when new keys are activated, preventing validators from avoiding removal penalties by simply replacing their keys. Additionally, the upgrade closes a loophole in BSC governance by preventing blacklisted addresses from participating indirectly through signed messages. These changes will prevent blacklisted addresses from using alternative routes to influence governance decisions, strengthening the network's security framework. Staking participants should pay particular attention to these changes, as tighter validator key rules could affect how certain staking operations are configured, and validators who don't adapt their setups could face penalties or exclusion from the active set.
BEP-675 represents the most significant technical improvement, optimizing block processing efficiency through improved transaction validation. According to BNB Chain's internal tests on QANet, the new block-building method reduced validator processing time from 125 milliseconds to 15 milliseconds. The upgrade increased transaction capacity from 1,237 TPS to 2,324 TPS while maintaining the 450 millisecond block time. Average block utilization improved from 46.35% to 84.15%, suggesting the network can handle busier periods more efficiently without increasing block speed. BNB Chain has stated a goal of doubling mainnet throughput during the second half of 2026, and these contract-level changes are a direct step in that direction.
The Pasteur upgrade has implications for American investors through regulated investment products. VanEck BNB ETF shares are registered for trading on Nasdaq under ticker VBNB, with the fund's registration becoming effective on May 27, 2025. According to an August 7 SEC filing, VanEck Digital Assets appointed BitGo Bank & Trust as a second custodian for the fund's BNB holdings, with the custody agreement signed on August 5. The upgrade affects regular users and most application developers minimally, while node operators and block builders are responsible for completing the software changes required for the network upgrade.
