# MANTRA Chain software exploit and network halt

> Live situation record from CLSTR: https://clstr.news/situations/mantra-chain-software-exploit-and-network-halt
> Updated: 2026-08-27T06:54:35.000Z. Sources: 24. Developments: 3.

MANTRA Chain, a Layer 1 blockchain, halted all network operations, including transactions, staking, and bridge operations, following a security exploit. The incident was attributed to a vulnerability in an upstream software dependency. The exploit caused significant market volatility, with the OM token dropping approximately 18.5% to an all-time low and trading volume increasing by nearly 600%.

The network has since resumed mainnet operations using version v8.4.0. The vulnerability was traced to the Cosmos EVM module, which had been upgraded shortly before the incident. While the project team stated that no user funds were exploited, developers have raised concerns regarding a lack of transparency concerning specific transaction hashes and the exact attack route.

Subsequent investigations revealed that the Cosmos EVM software stack exploit resulted in a loss of approximately $5.72 million across at least six networks, including MANTRA, TAC, and KiiChain. The vulnerability was identified as an “arithmetic underflow occurring when mirroring balances after staking operations.” 

Cosmos Labs reported that while the flaw was identified on April 25, engineers mistakenly believed production chains were safe because they used 18 decimals rather than the six-decimal format used during initial testing. This misjudgment left multiple networks exposed for months. While the Cosmos Hub and ATOM tokens were not directly targeted, the shared software layer allowed attackers to move significant funds. In response, Cosmos Labs contacted 40 networks, and several chains have since patched or halted operations to mitigate further risk.

## Timeline

### 2026-08-27: Cosmos EVM exploit drains nearly $6 million across multiple networks

Hackers exploited a long-standing Cosmos EVM vulnerability to steal nearly $6 million across multiple blockchain networks, including MANTRA and KiiChain, after a misjudgment regarding decimal precision.

5 sources. https://clstr.news/cluster/cosmos-evm-exploit-drains-nearly-6-million-across-multiple-networks

### 2026-08-27: MANTRA Chain resumes operations after software dependency exploit

MANTRA Chain has resumed operations via version v8.4.0 after a network halt caused by an upstream software exploit in its Cosmos EVM module. Developers have raised concerns over transparency and undocumented 코드

2 sources. https://clstr.news/cluster/mantra-chain-resumes-operations-after-software-dependency-exploit

### 2026-08-21: MANTRA Chain halts network operations following software exploit

MANTRA Chain has halted all transactions and network operations after an attacker exploited an upstream dependency vulnerability, causing the native token to drop to an all-time low.

18 sources. https://clstr.news/cluster/mantra-chain-halts-block-production-following-unexplained-incident

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Cite as: MANTRA Chain software exploit and network halt. CLSTR, https://clstr.news/situations/mantra-chain-software-exploit-and-network-halt