Swiss cryptocurrency exchange SwissBorg suffered a significant security breach on September 8, 2025, resulting in the theft of approximately $41.5 million worth of Solana (SOL). Hackers exploited a vulnerability in a partner API provided by Kiln, which compromised SwissBorg's SOL Earn staking program and drained around 193,000 SOL. The incident affected less than 1% of the firm's user base, but it represents a substantial portion of its Solana holdings, estimated at $72.6 million total.
CEO Cyrus Fazel addressed the hack in a live broadcast, stating, 'SwissBorg has not been hacked. There is an external attack from a provider that was unfortunately compromised.' He confirmed that the main application and other staking programs remain secure. The stolen funds account for about 2% of SwissBorg's assets under management, and the company has allocated treasury funds to reimburse users, promising a significant portion of their balances even without full asset recovery.
White-hat hackers, security partners like Fireblocks and the Solana Foundation, and multiple exchanges are assisting in tracking and blocking transactions related to the hack. Fazel emphasized the emotional impact on users and committed to transparency, additional security measures, and law enforcement collaboration. This event highlights ongoing concerns about API exploits in crypto, as warned by investigator ZachXBT regarding a 'crime supercycle'.
