Ostium Hit by $18 Million Exploit Amid Ongoing Oracle Attacks in DeFi

Ostium's price-feed system was compromised, leading to an $18 million USDC theft.

Ostium, a decentralized perpetuals exchange on Arbitrum, experienced a significant security breach that resulted in the theft of approximately $18 million in USDC. The attack involved the manipulation of the platform's price-reporting system, where the hacker submitted fraudulent oracle data with future timestamps, creating a false appearance of profitable trades.

This exploit follows a series of recent attacks targeting oracle and keeper systems within the DeFi sector, including a notable $6 million incident at Summer.fi. The ongoing vulnerabilities in these automated systems, which provide essential real-world price data, are raising alarms among industry stakeholders.

According to findings from blockchain security firm Blockaid, the attacker utilized a registered PriceUpKeep forwarder—integral to Ostium's infrastructure—to submit manipulated pricing reports. These deceptive reports misled the system into triggering the substantial payout.

Before this exploit, Ostium had successfully raised $27.8 million in funding, including a $24 million Series A round co-led by General Catalyst and Jump Crypto in late 2025, and had facilitated over $50 billion in trading volume.

The platform offers leveraged trading on real-world assets like commodities and forex, settling transactions in USDC. Its unique price-feed mechanism relies on a third-party network, Gelato, to ensure that accurate price data is pushed onchain at crucial moments. The PriceUpKeep smart contract is vital for updating the blockchain with current price information during trades.

This incident highlights the persistent risks associated with oracle manipulation in decentralized finance, as attackers increasingly exploit privileged roles to alter price data and extract funds from liquidity pools.