EVM network halts block production after supply exploit as TON connection remains dark

TAC, an EVM network connected to TON, halted validator block production after the project said an exploited vulnerability affected the Cosmos-based EVM side of its network and, according to TAC, only the TAC token supply.

In an Aug. 22 notice, the team said it was working with validators on a temporary halt that would take effect within minutes. TAC’s official Telegram announcement channel subsequently described the halt as implemented and promised further findings and steps toward resuming the chain.

A check of the TAC explorer API at about 1:03 p.m. UTC on Aug. 23 returned block 24,671,475, timestamped 11:58:11 p.m. UTC on Aug. 22, as the latest block. A fresh check of the TAC explorer at about 7:58 a.m. UTC on Aug. 24 still showed block 24,671,475.

TAC’s notices did not identify an unauthorized TAC amount, a dollar loss, the exploit transaction or block height, the vulnerable component, affected wallets, user losses or a restart timetable. The team also did not explain why the problem could not be isolated below the full-chain level.

The halt raises a state-reconciliation question that TAC has not yet answered. The project has not said whether native, wrapped, bridged, staked, exchange-held or protocol-controlled TAC balances must be checked before validators agree on a canonical state, and the available evidence does not establish that every one of those categories was affected.

The scope differs from TAC’s separate May 11 bridge breach. In its May 20 post-mortem, TAC said its sequencer software failed to verify both the code hash of a TON jetton, or token, wallet and the expected minter behind it. Counterfeit deposit messages were accepted, unbacked equivalents were issued on TAC, and genuine assets locked on TON were released through the normal return path.

TAC put the May incident’s total protocol loss at approximately $2,854,486.22 as of May 12 at 10 p.m. UTC. During that response, it halted the sequencer set connecting TAC to TON while saying the TAC EVM layer remained fully operational.

The latest validator-coordinated chain halt is therefore a broader operational response, but it does not establish a new loss figure or show that the two incidents share a root cause. Until TAC publishes technical details of the Aug. 22 supply incident and a reconciled supply figure, the defensible conclusion is limited: block production was stopped, TAC says the issue concerns only its token supply, and the conditions for resuming remain undisclosed.