MANTRA Chain (Cosmos EVM precompile) hack — August 2026

MANTRA stopped producing blocks late on 20 August 2026, the first of six chains hit through the same defect in the shared cosmos/evm staking precompile. It was also the largest single loss in that campaign: 720.9m MANTRA tokens, worth about $3.6m at the time, taken from two addresses that The Block identifies as a burn address and a dormant multisig. Roughly 94.7% of it was converted to proceeds through a centralised exchange, which is an unusually high conversion rate for the group and reflects how much deeper this token's liquidity was than TAC's or KiiChain's.

The chain resumed at about 05:30 UTC on 22 August after a coordinated validator restart on version 8.4.0, which carried the patch. MANTRA said user balances were not altered and that there was no rollback between the halt and the resumption, and its public statements throughout described no user funds as lost.

Both things are true and the entry records both. No individual holder was made poorer, which is what the project's statements address. Tokens that the protocol had placed beyond use were nonetheless moved by an attacker and sold into the market for real money, which is what the recorded figure measures. The registry counts assets removed from where their owner had put them, and a burn address is a place an owner puts something intending it to stay there.

The defect was not MANTRA's own code. Cosmos Labs received the vulnerability report in April 2026, judged that production networks were not at risk, and handled it through a silent patch; it later said that assessment was wrong.