Venus $THE Exploit Analysis
A recent incident on the Venus lending protocol involved a classic price manipulation strategy similar to the Mango Markets attack model, targeting the low-liquidity collateral asset THE. The exploit demonstrates how thin liquidity combined with oracle mechanics can be used to artificially inflate collateral value and expand borrowing power.
Attack Overview
The attacker focused on THE, a collateral asset with extremely limited on-chain liquidity. Because the token traded in shallow markets, relatively small capital flows were sufficient to significantly move its price.
The strategy followed a recursive borrowing loop commonly seen in DeFi oracle manipulation attacks:
- Deposit THE as collateral on Venus
- Borrow other assets against that collateral
- Use the borrowed assets to buy more THE in the open market
- Push the token’s price higher through repeated purchases
- Wait for the time-weighted oracle to update the price
- Receive higher collateral valuation from the protocol
- Repeat the cycle to increase leverage
Because liquidity was extremely thin, the market price of THE moved from roughly $0.27 to nearly $5 during the manipulation phase.
However, Venus relied on a time-weighted average price oracle, which meant the price update did not immediately reflect the extreme spike.
When the oracle updated, the reported price settled around $0.50, still significantly higher than the original market value.
This increase allowed the attacker to expand borrowing capacity further.
Bypassing the Supply Cap
THE had a supply cap within the Venus market, intended to limit how large a collateral position could grow.
This restriction normally prevents attackers from endlessly expanding leveraged positions.
The attacker bypassed this restriction using a well-known Compound-fork technique known as the donation attack.
After depositing a large amount of THE into the protocol, additional tokens were sent directly to the vTHE contract. Because of the way Compound-style markets account for collateral balances, these direct transfers effectively increased the collateral value recognized by the system, allowing the attacker to continue expanding the position beyond the intended limits.
This maneuver significantly amplified the attacker’s effective borrowing capacity.
Position Expansion and Market Impact
After the initial manipulation phase, the price of THE stabilized around $0.50 according to the oracle.
At this stage the attacker already held a heavily leveraged position backed by inflated collateral value. However, the strategy continued in an attempt to further increase the token’s market price.
This phase encountered a major structural constraint: market liquidity.
Although the price had been pushed upward, the market began experiencing significant selling pressure. Each additional purchase required more capital to sustain the price movement, and the attacker’s buying activity gradually lost its ability to move the market upward.
As the position expanded, the account’s health factor began deteriorating, eventually approaching the liquidation threshold.
Liquidity Mismatch
At the peak of the attack, the attacker controlled collateral with a nominal value of roughly $30 million based on the oracle price.
However, the majority of this collateral consisted of THE tokens accumulated during the manipulation process, and the market lacked sufficient liquidity to absorb such a large position.
This created a critical mismatch:
The protocol evaluated the collateral using the oracle price, but the actual market depth was insufficient to support liquidation at that valuation.
If liquidation occurred, the system would need to sell large amounts of THE into a very thin market, forcing the price downward rapidly.
Liquidation and Aftermath
Once the position’s health factor approached the liquidation threshold, the system began unwinding the position.
As the collateral entered the market, THE experienced heavy downward pressure, with the price eventually falling to around $0.24, below its pre-attack level.
The decline was amplified by both liquidation sales and existing holders exiting their positions.
Following the event, Venus was left with approximately $2 million in bad debt, highlighting the systemic risks associated with illiquid collateral assets.
Key Lessons
This incident highlights a recurring structural issue in DeFi lending systems:
Nominal collateral value does not equal realizable liquidation value.
Protocols typically calculate collateral value using oracle prices, but if the collateral asset lacks sufficient liquidity, the system may drastically overestimate the amount that can actually be recovered during liquidation.
In cases where collateral assets have thin markets and limited depth, a protocol may see tens of millions in collateral value while the market can realistically absorb only a small fraction of that amount.
The Venus THE exploit serves as another example of how low-liquidity collateral, oracle lag, and recursive leverage loops can combine to create systemic risk in decentralized lending markets.