MANTRA Chain Halted for 30 Hours Due to Cosmos-EVM Vulnerability

MANTRA Chain's mainnet was temporarily halted on August 20 after an attacker targeted its EVM module, exploiting a vulnerability in an upstream software dependency. The incident lasted for approximately 30 hours, with block production resuming at around 5:30 a.m. UTC on August 22 after developers deployed version 8.4.0 to fix the issue.

The patch, which also added security protections, was tested on the DuKong testnet before being validated in an internal environment that replicated the mainnet state. MANTRA-operated validators were upgraded first, followed by validator partners and other node operators.

Two MANTRA-managed wallets were affected by the attack, but user balances remained unchanged. The project has not disclosed what activity occurred in these wallets or how much value was involved. A complete post-incident report is expected to be published in the coming days.