BNB Chain Activates Pasteur Hard Fork to Boost Security

Pasteur hard fork goes live on BNB Smart Chain

BNB Chain has activated the Pasteur hard fork on its mainnet as scheduled. The upgrade, timed for 02:30 UTC on August 25, focuses on improving cross-chain bridge security, tightening validator key management, and making better use of each block’s capacity rather than further shortening block times. Node operators were required to upgrade their clients to version 1.7.7 before the activation.

Three BEP proposals under BEP-673

Pasteur brings three technical changes grouped under BEP-673. These proposals target common pain points for blockchain interoperability and on-chain security, especially in bridge validation and validator operations.

BEP-682 — Preventing duplicate validator entries

The first change, BEP-682, removes duplicate validator identities when validating light blocks used by cross-chain bridges. Before the upgrade, a manipulated validator set could include the same validator name multiple times and have that validator’s voting power counted repeatedly. The new logic ignores repeated IDs so asset transfers across the bridge require only the genuine number of signatures, strengthening bridge security and reducing attack surface for signature-based manipulations.

BEP-695 — Stricter consensus key rotation

BEP-695 enforces a more rigorous process for consensus key rotation. After a key rotation, the retired validator key should no longer retain signing authority and any pending responsibilities are transferred to the new key. This reduces risks from retired or compromised keys and helps preserve staking and governance continuity by ensuring key-management best practices are enforced.

BEP-675 — Faster block delivery and better block filling

BEP-675 introduces a new route for block propagation from builders to validators. Internal QANet testing showed throughput improvements under controlled conditions, increasing processing capacity from roughly 1,237 to 2,324 transactions per second. These figures reflect test conditions and should not be interpreted as guaranteed mainnet performance; the primary goal is to pack blocks more effectively within the existing block interval to increase usable throughput.

What users and developers should know

For ordinary users, no asset migration or immediate action is required; the changes operate behind the scenes. Developers should also see minimal backward-incompatible impact. The most significant responsibilities fall to validators, node operators, and block builders who must follow the upgraded client and updated key-management procedures. Real-world impact on block capacity and TPS will become clear as the network is observed under peak traffic and post-activation metrics are collected.

Overall, the Pasteur hard fork is an incremental but important security and performance-focused upgrade for BNB Chain, emphasizing safer bridge operations, robust validator key hygiene, and improved block utilization to support higher on-chain throughput.