Cronos Network Halts for Over 10 Hours After Tectonic Exploit, $68.7 M Remains Frozen

Cronos, the Cosmos‑SDK based Layer 1 backed by Crypto.com, stopped producing blocks for more than ten hours on Sunday after a massive exploit of the Tectonic lending protocol. The halt froze roughly $68.7 million of stolen assets on the chain, with only about $6.29 million transferred to Ethereum before the network was paused.

Network Outage and Block Freeze

Lookonchain captured the Cronos explorer at 9:11 p.m. ET showing the latest transaction in block 90,907,150, timestamped “10 hrs 36 mins ago.” No new block had been produced since, indicating a full network halt. Cronos did not provide a timeline for resumption.

Scale of the Exploit

• Security firm PeckShield identified three attacker addresses holding about $74 million in assets.
• Researcher Weilin Li estimated the loss at over $75 million.
• Cronos ambassador “Hajedan” calculated total borrowing of $124.96 million across 16 Tectonic markets, with $110.5 million still on Cronos and $7.8 million unaccounted for.

Funds Flow

Approximately $6.29 million was bridged to Ethereum and swapped for 2,592 ETH. The remaining assets are locked on Cronos, primarily in USDT/USDC liquidity on VVS Finance.

Mechanics of the Attack

The attacker deployed a contract that executed the exploit within its constructor, completing the extraction by 9:07 a.m. ET. Two simultaneous inflations occurred:

1. In 98 rounds, the attacker borrowed the entire cash balance of the tTONIC market and returned it as a plain token transfer, inflating the market’s exchange rate eightfold in a single block.
2. USDC borrowed earlier was used to purchase TONIC on VVS pools, draining TONIC reserves and pushing the oracle price up roughly 195 times, resulting in collateral valuations up to 1,568 times their true worth.

Impact on Tokens

TONIC’s circulating market cap was about $8.09 million at the time, far below the $75 million borrowed against it. Tectonic’s total value locked fell to roughly $3.0 million, a 97 % drop from its pre‑attack peak.

Responses

Crypto.com’s CEO Kris Marszalek confirmed the breach was limited to the Tectonic protocol and that the Crypto.com app and exchange remain unaffected. Cronos has not announced a restart schedule, nor have Tectonic or Cronos disclosed official loss figures or remediation plans for depositors.