On Sept. 25, the attacker also accessed the management platform of a second security product, which SlowMist called “Product B,” using an internal employee’s identity. SlowMist said the attacker then attempted to inject system commands, alter server configurations and upload malicious program files.
SlowMist said its investigation remains ongoing and that it is still examining how the attacker moved between the affected systems.
Attacker used custom withdrawal tool
The security company said it recovered a deleted, highly customized tool used to manipulate the wallet system’s withdrawal process. The tool forged risk-control parameters, constructed withdrawal requests and invoked the withdrawal process.
SlowMist’s onchain verification found the earliest transfer verified to date at 2:31 am UTC+8 on Sept. 25, when an attacker-controlled address received 93 TRX, followed 11 seconds later by 0.84 Ether on Ethereum. The compiled transfer records spanned about two hours and 52 minutes across multiple blockchains, extending to 5:23 am that day.
The attacker also tried to modify withdrawal records directly in the wallet database and trigger additional Bitcoin withdrawals. SlowMist said two fabricated BTC withdrawal orders entered processing but returned errors, after which the attacker reviewed logs, checked order status and made further attempts.
In a Sept. 25 update, Bitget said about $387.5 million was transferred to attacker-controlled addresses across several networks.
Bitget CEO Gracy Chen later told Cointelegraph that the breach stemmed from a vulnerability in a third-party security product that allowed the attacker to obtain “high-level internal credentials” and issue fraudulent withdrawal commands. She said Bitget’s private keys and cold wallets were not compromised.
Bitget is still trying to recover the stolen assets. Speaking on Cointelegraph’s Chain Reaction, Chen said she was “not very optimistic” about fully recovering the roughly $388 million lost, pointing to the limited recovery from Bybit’s 2025 hack as a reference point.