TLDR
- A misconfigured oracle caused Coinbase Wrapped ETH (cbETH) to be mispriced at $1 instead of its actual value of $2,200.
- The error led to widespread liquidations and left Moonwell with $1.8 million in bad debt.
- Moonwell quickly acted by reducing the borrow and supply caps to prevent further damage.
- Exploiters took advantage of the mispricing to over-borrow cbETH and generate additional bad debt.
- Moonwell plans to address the oracle configuration issue in an upcoming governance vote.
A pricing glitch caused by a misconfigured oracle has left the decentralized finance (DeFi) lending platform Moonwell with $1.8 million in bad debt. The error occurred when Coinbase Wrapped ETH (cbETH) was briefly priced at just $1, far below its actual value of around $2,200. This mistake triggered mass liquidations and resulted in a severe financial loss for the platform.
Misconfigured Oracle Causes Disastrous Price Deviation
On February 15, at 6:01 PM UTC, Moonwell’s oracle misconfigured its pricing system, leading to the massive price discrepancy. The misconfiguration happened after the Moonwell DAO governance proposal, MIP-X43, was executed. This proposal enabled Chainlink OEV wrapper contracts across various markets on Base and Optimism.
Instead of correctly multiplying the cbETH/ETH price feed by the ETH/USD price, the system used only the raw cbETH/ETH exchange rate. The error caused the oracle to report cbETH at just over $1, leading to a significant mispricing of assets. As a result, the lending platform saw liquidators target positions based on this faulty pricing.
Moonwell’s Response to the Oracle Mishap
Upon detecting the error, Moonwell’s risk manager, Anthias Labs, acted quickly to contain further damage. The team reduced the cbETH borrow cap to 0.01, limiting the amount of affected collateral that could be used. Additionally, they lowered the supply cap to 0.01 to prevent new users from supplying to the impacted market.
Despite these measures, the damage was already done. Liquidators repaid approximately $1 of debt and seized 1,096.317 cbETH, leaving borrowers with almost no collateral. As a result, Moonwell was left with approximately $1.8 million in bad debt, according to a Moonwell forum post shared by Anthias Labs.
Exploitation of the Distorted Pricing Leads to Further Losses
The misconfigured Oracle not only caused widespread liquidations but also enabled exploitation. A few users exploited the distorted pricing by supplying minimal collateral and over-borrowing cbETH at the artificially low price. This led to further bad debt, compounding Moonwell’s financial troubles.
The incorrect pricing data allowed users to borrow more than they should have, leveraging the system’s flaw to create additional bad debt. Following this, Moonwell announced plans to address the oracle configuration in an upcoming governance vote after the necessary timelock period.
