Cronos Halts Blockchain After Estimated $75M Tectonic Exploit

Cronos's blockchain was halted on Sunday after an exploit in its largest lending protocol, Tectonic, which resulted in an estimated loss of $75 million. The attacker manipulated the price of TONIC, Tectonic's governance token, pushing it roughly 100-fold higher in about 20 minutes.

Weilin Li, an independent researcher, initially estimated the attacker had captured around $66 million before discovering a second attacker-controlled address holding approximately $8 million more. This raised his total estimate to around $75 million, with most of the funds staying on Cronos and only about $6 million reaching Ethereum before the halt.

Cronos runs on Tendermint consensus, which allows for an emergency pause operationally realistic, enabling the network to trap most of the exploit-linked funds. However, this also froze every other open position, pending transaction, and smart-contract call on Cronos, not just the attacker's, until the halt is lifted.

Tectonic held about $121.7 million in total value locked and roughly $82.7 million in active loans immediately before the exploit, according to DefiLlama. Neither Cronos nor Tectonic has released an official cause or a final loss figure as of Monday.