TAC halts block production after 2nd exploit, TON link dark

TAC halted validator block production at block 24,671,475 on Aug. 22 after an exploit hit its token supply, with the TON connection still dark.

Checks of the TAC explorer API at 1:03 p.m. UTC on Aug. 23 and again at 7:58 a.m. UTC on Aug. 24 both returned block 24,671,475, timestamped 11:58:11 p.m. UTC on Aug. 22, as the latest block. TAC's official Telegram announcement channel described the halt as implemented and promised further findings and steps toward resuming the chain.

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, a gap that leaves users unable to assess exposure.

The halt is broader than TAC's May 11 bridge breach, when the project halted only its sequencer set connecting TAC to TON while the EVM layer stayed live. That incident cost the protocol about $2,854,486.22, per its May 20 post-mortem, which found the sequencer failed to verify the code hash of a TON jetton wallet and its expected minter.

State reconciliation remains unresolved

TAC, an EVM network built on the Cosmos SDK that connects to TON, has not answered a state-reconciliation question raised by the halt. 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 category was affected. Without a reconciled supply figure, validators cannot confirm which balances are legitimate before restarting.

A broader run of chain-level failures

TAC is the latest network to stop block production during a concentrated run of security failures. MANTRA Chain resumed block production Aug. 22 after a roughly 30-hour halt tied to a Cosmos-EVM vulnerability. KiiChain halted after an EVM-module exploit moved funds through Hyperlane to BNB Smart Chain, and BounceBit permanently retired its Layer 1 after a $3 million BB exploit.

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. The lack of a restart timetable adds uncertainty for users holding TAC balances across exchanges, bridges and staking protocols, and for the TON connection that remains non-functional.

This article is for informational purposes only and does not constitute investment advice.