On Arbitrum, Ostium, a decentrified and lasting contract platform, was attacked by a prophecies machine, and about 18 million USDCs were transferred out of the protocol's mobile treasury. Blockaid, a chain-based security company, stated that the attackers had triggered unusual payments by submitting false data with a future time stamp, using registered components in their price reporting process.
The attack used the price to report the components.
Ostium provides, inter alia, long-term transactions linked to real-world assets, including gold, foreign exchange and equity indices, with the settlement of assets as USDC. The agreement is deployed on Arbitrum and supports a maximum of 200 times leverage.
According to public information, Ostium uses a custom-defined price-feeding system to track real world asset prices and uses a third-party automated network of Gelato to write prices on the chain at certain points in time. The contract at the core of the process, called PriceUpKeep, is responsible for triggering the latest price up-to-chain at the time the transaction is executed.
Blockaid states that the attackers used a registered PriceUp Keep forwarder. By submitting altered prognosis data to the system with a future time stamp, the attackers created the illusion of profit from the trade and eventually extracted about 18 million USDCs from the agreed vault.
Recreate the keeper and the prophecy loophole
The incident continued the course of the recent re-emergence of Keeper and Prophetic attacks in DeFi. Such attacks usually do not directly tamper with market prices per se, but instead manipulate the timing or content of the price data and draw funds from the mobility pool, using automated components with specific competencies.
Just last week, Summer.fi lost about $6 million for similar problems. Successive events have shown that the chain-based automation and feeding infrastructure on which many agreements depend remains a weak link in DeFi security.
Ostium previously financed $27.8 million
Before the incident, Ostum had accumulated $27.8 million in financing. Of this, round A, completed at the end of 2025, was on a 24 million dollar scale and was co-sponsored by General Catallyst and Jump Cripto.
Public data show that Ostium had previously accumulated over $50 billion in transactions. The attack not only resulted in financial losses, but also affected the market ' s assessment of RWA ' s ability to keep trading agreements under control.