MANTRA Chain restored mainnet block production on v8.4.0 after a security incident forced a six-day chainwide halt, while OM later surged sharply on South Korean exchanges. The network returned without a rollback, but MANTRA still has not published the promised technical postmortem.
MANTRA's incident timeline says mainnet resumed at about 05:30 UTC on Aug. 22. The chain reported no rollback or state change between the halt and restart. MANTRA also said user balances remained unchanged and token holders did not need to act. The team marked the incident resolved on Aug. 24.
Still, the status page and official announcement channel showed no postmortem link when checked on Aug. 27. The team had again said that report would arrive in the coming days. For node operators, the public code record points to one immediate check. MANTRA's current release page lists full commit 5c08d7bd9e2619952707dae1258d2a30bf024721.
The chain also warned operators that the team re-pushed the v8.4.0 tag during recovery. As a result, operators need to identify which v8.4.0 build their nodes currently run.
MANTRA said its analysis found activity inside two project-managed wallets. It also said the incident did not affect user, exchange, or partner funds. Yet the public account does not identify the wallet addresses, transaction hashes, amounts, or exact exploit steps. Those missing details prevent users from tracing the disclosed wallet activity through public records. That leaves one pivotal question: how did the attacker exploit the upstream dependency and move through the two MANTRA-managed wallets?
The release changelog shows an intermediate MANTRA EVM fork bump from v0.6.0-v8-mantra-3 to v0.6.0-v8-mantra-4. The final tagged go.mod instead uses the chain's v0.6.2-v8-mantra-1 fork.
The final upgrade handler also blocklists one address and disables three Cosmos vesting-account creation messages through the circuit breaker. Those measures describe MANTRA's deployed mitigation but not the attack path.
Meanwhile, a March Cosmos Labs advisory described a critical ICS20 precompile flaw and named Mantra among remediation collaborators. The advisory ends with the March disclosure and does not document the August incident.
Read More: MANTRA Chain Halts Network After Exploit Sends Token to Record Low
OM surged during intraday trading on Aug. 28 following MANTRA's earlier security disruption. On Bithumb, the token traded at 14.83 won at 8 p.m., up 142.68% from a day earlier. The token had reached 18 won earlier in the session. Meanwhile, Upbit quoted OM at 8.53 won, representing a 47.32% daily gain.
The gap between South Korea's two major exchanges widened further against global pricing. CoinMarketCap showed OM at 6.11 won at the same time, up 5.96% from a day earlier.
Therefore, users can verify the restart, final code, and MANTRA's stated impact. Wallet addresses, transaction hashes, affected amounts, exploit steps, and any ICS20 connection remain outside the public record.
MANTRA Chain has resumed block production on v8.4.0 and said user funds remained unaffected. OM then surged sharply on South Korean exchanges. Still, MANTRA has not published the promised postmortem, wallet addresses, transaction hashes, affected amounts, exploit steps, or evidence linking the August incident to ICS20.