What Is Cetus Protocol? Sui's Largest DEX, the $223M Exploit and xCETUS
Cetus is Sui's largest AMM. How its concentrated liquidity works, what caused the $223M May 2025 exploit, how users were repaid, and how CETUS and xCETUS work.
Short answer: Cetus is the largest AMM-style decentralised exchange on Sui. It's a concentrated liquidity market maker (CLMM): liquidity providers choose the price range their capital trades in. It launched on Aptos in late 2022 and on Sui at mainnet in May 2023. In May 2025 it lost $223M to an exploit in a shared maths library. Most of the funds were frozen and recovered through a Sui governance vote. As of 16 September 2026, Cetus holds $23.4M of TVL and handles about 30% of all DEX volume on Sui.
This guide covers how Cetus works, what happened in the exploit and how the recovery was funded, how CETUS and xCETUS work, and what the numbers look like today.
The Cetus exploit didn't come from a novel attack on concentrated liquidity. It came from one wrong constant in an overflow check. That's the part worth remembering.
How Cetus works
Cetus runs several products on one liquidity base:
- CLMM pools. The core product. Like Uniswap v3, LPs deposit two tokens within a price range they choose. Inside that range their liquidity is many times deeper than in a full-range pool, so they earn more fees per dollar. When the price leaves the range, the position stops earning and ends up holding only one of the two tokens. The mechanics are in our concentrated liquidity explainer.
- DLMM pools. Launched in autumn 2025. Liquidity sits in discrete price bins, and swaps inside one bin have zero price impact. It's still small next to the CLMM, at $0.3M of TVL and $8.5M of 30-day volume.
- An aggregator that routes swaps across Cetus and other Sui venues for the best price.
- Incentive programmes that pay extra token rewards to LPs in selected pools, on top of trading fees.
Because Cetus pools are the default home for many Sui tokens, a lot of the chain's other activity runs through them: new token launches, lending liquidations and automated yield vaults.
The May 2025 exploit
On 22 May 2025, an attacker drained about $223M from Cetus's CLMM pools. It was one of the largest DeFi exploits of the year, and the biggest security event in Sui's history.
What went wrong
The bug wasn't in Cetus's trading logic. It was in checked_shlw, a function in integer-mate, a shared library for 256-bit integer maths. The function should abort whenever shifting a number left would overflow. Its check compared against the wrong constant, so certain oversized values passed.
The attacker used that gap in the maths that converts a liquidity amount into the tokens needed to back it. They opened a position in a very narrow, extreme price range and funded it with a flash swap. The overflowing calculation truncated, so the position was credited with a huge amount of liquidity for almost no deposit. Removing that liquidity then paid out real tokens from the pool.
Security firms including BlockSec, Dedaub and Cyfrin published detailed post-mortems. The lesson for users: an audited protocol still depends on every library under it, and in concentrated liquidity the dangerous code is the arithmetic.
How much was recovered
About $162M of the stolen funds was still on Sui when validators froze the attacker's addresses. Roughly $60M had already been bridged to Ethereum.
Freezing assets on a supposedly permissionless chain was controversial. Returning them needed a protocol-level upgrade, so it went to a vote. Sui validators approved the recovery proposal on 29 May 2025 with about 90.9% of stake voting yes.
How users were paid back
The recovered funds didn't cover the part that had left Sui. Cetus filled the gap with:
- about $7M of its own treasury cash;
- a 30M USDC loan from the Sui Foundation;
- 15% of CETUS supply set aside for affected users: 5% at once and 10% vesting over 12 months from 10 June 2025.
Cetus relaunched on 8 June 2025. LPs in affected pools got back between 85% and 99% of their positions depending on the pool, and the CETUS allocation covered the rest over time. It was one of the more complete recoveries after a nine-figure exploit. It also depended on validators being willing to freeze funds, which is not something users of most chains can count on.
CETUS and xCETUS
CETUS is the protocol's tradable token. On 16 September 2026 it traded around $0.0197 with a market cap of about $18.9M (CoinGecko).
xCETUS is an escrowed, non-transferable version. You get it by staking CETUS 1:1. It earns a share of protocol rewards, carries governance weight and boosts LP farming rewards. You can't sell it. To turn xCETUS back into CETUS you start a redemption, and the rate depends on how long you're willing to wait:
| Vesting period chosen | CETUS received per xCETUS |
|---|---|
| 15 days (minimum) | 0.5 |
| Between 15 and 180 days | Scales between 0.5 and 1.0 |
| 180 days (maximum) | 1.0 |
Whatever you give up with a shorter vest goes to Cetus's eco treasury, and you can cancel a redemption before it finishes. In practice, xCETUS is a long-term commitment. Anyone who needs liquidity has to either wait six months or lose up to half.
That lock is why liquid wrappers exist. JWLCETUS, JewelSwap's CETUS derivative, is minted 1:1 from CETUS. JewelSwap converts the CETUS it receives to xCETUS, and the governance-staking rewards are swapped into JWLCETUS and paid to JWLCETUS stakers every 7-day epoch. JWLCETUS is unredeemable: you can't turn it back into CETUS through the protocol. You exit by selling it on the market, where the rate can differ from 1:1. That trade-off is the whole point of it, and it's covered in the JWLCETUS docs.
Cetus by the numbers (16 September 2026)
| Metric | Value | Context |
|---|---|---|
| CLMM TVL | $23.4M | Largest AMM on Sui |
| Peak CLMM TVL | $268.0M | 23 November 2024 |
| TVL day before exploit | $238.1M | 21 May 2025 |
| 30-day volume | $392.6M | 29.8% of Sui DEX volume |
| 30-day fees | $588k | Highest of any Sui DEX |
| CETUS price | ~$0.0197 | Market cap ~$18.9M |
The pattern is a DEX that kept its role but not its liquidity. Cetus still has the highest fee income and joint-highest volume on Sui. Its TVL, though, is less than a tenth of its peak. For traders that means checking depth pool by pool. For LPs it means more fees per dollar deposited, with the extra price risk that thin pools bring. Our Sui DEX comparison puts Cetus next to DeepBook, Bluefin, Turbos and Momentum.
Using Cetus: what to check first
- Pool depth and price impact. Look at the price impact before you confirm a swap. With DEX liquidity this thin, an aggregator often gets a better price than trading on one pool directly.
- Which pool you're in. The same pair can exist at several fee tiers. Liquidity is usually concentrated in one of them.
- Your range, if you LP. A narrow range earns more while in range and loses more when price leaves it. Decide how often you'll rebalance before you deposit, not after.
- What the reward token is worth. Incentive APRs paid in CETUS depend on CETUS's price, which has been under heavy pressure.
- Automation, if you don't want to manage it. JewelSwap's Cetus farms harvest rewards and re-add liquidity every 30 minutes on ten pools, including USDC–SUI, CETUS–SUI and DEEP–SUI. They run at 1× leverage with a 15% performance fee on harvested rewards. Two-asset pools still carry impermanent loss.
Frequently asked questions
What is Cetus Protocol?
Cetus is a decentralised exchange and concentrated liquidity protocol on Sui, and originally Aptos. It's the largest AMM on Sui by TVL and one of the two highest-volume DEXs on the chain.
Was Cetus hacked?
Yes. On 22 May 2025, an attacker took about $223M by exploiting an overflow-check bug in the integer-mate maths library that Cetus used. About $162M was frozen on Sui and returned after validators approved a recovery proposal, and Cetus relaunched on 8 June 2025.
Did Cetus users get their money back?
Mostly. Affected LPs recovered 85–99% of their positions at relaunch. The recovery was funded by frozen assets, about $7M of Cetus treasury cash and a 30M USDC loan from the Sui Foundation. 15% of CETUS supply was also set aside for affected users, vesting through June 2026.
What is xCETUS?
xCETUS is a non-transferable, escrowed form of CETUS that earns protocol rewards, carries governance weight and boosts farming rewards. Redeeming it to CETUS takes between 15 days (at 0.5 CETUS per xCETUS) and 180 days (at 1:1).
Is Cetus safe to use now?
The specific bug was fixed and the protocol has run since June 2025. No DeFi protocol is risk-free, and the exploit showed that risk can sit in a dependency, not the protocol's own code. Keep positions sized so a protocol failure is survivable, and check pool depth before trading.
What is JWLCETUS?
JWLCETUS is a liquid CETUS derivative from JewelSwap. It's minted 1:1 from CETUS, which JewelSwap stakes as xCETUS, and stakers receive rewards every 7-day epoch. It can't be redeemed back to CETUS through the protocol. Holders exit by selling it on the market.
Keep reading
- Sui DEXs compared: Cetus, DeepBook, Bluefin, Turbos and Momentum
- Concentrated liquidity (CLMM) explained
- How to check a DeFi protocol before you deposit
- Best DeFi platforms on Sui in 2026
- DeFi composability: why money legos cut both ways
This article is educational and isn't financial advice. TVL, volume and fee figures are from DefiLlama and the CETUS price is from CoinGecko, both on 16 September 2026. Exploit and recovery details are from Cetus's announcements and published third-party post-mortems. JewelSwap operates Cetus-based vaults and the JWLCETUS token and has an interest in Cetus.
