BounceBit Shuts Down Layer 1 Blockchain After $3 Million Token Exploit

BounceBit is permanently shutting down its standalone Layer 1 blockchain after an attacker exploited a protocol-level authorization flaw, transferring around $3 million in BB tokens. The security incident occurred between August 19 and 20, when an attacker executed 14 unauthorized transactions involving nine BounceBit mainnet accounts.

The company will reissue the BB token as a BEP-20 token on the BNB Chain using pre-attack balances, automatically restoring legitimate balances while removing transfers caused by the exploit. The new token issuance process excludes the 286.5 million BB tokens held by the attacker from the calculations.

BounceBit chose to migrate to BNB Chain instead of rebuilding its existing blockchain due to the difficulty in maintaining a standalone Layer 1 network, as Evmos, the underlying technology behind its network, was discontinued in May 2026.