KiiChain Cosmos EVM Balance-Handling Underflow Exploit — 148.3M KII

On August 22, 2026 (starting around 20:32 UTC), an attacker repeatedly exploited the same shared Cosmos EVM vulnerability (GHSA-7g4w-cg88-2cq2) already described for TAC, launching 18 separate exploit attempts against KiiChain. KiiChain's own post-mortem confirmed a total of 148,326,583.15 KII extracted, valued at roughly $9.7M nominal / $1.61M realized after conversion. This is the same shared-module underflow bug (a precomputed vesting account address, contract inheriting vesting status, then over-delegation triggering an integer underflow) exploited across MANTRA (the first victim, August 20, outside this reporting window), TAC and Nesa within this window.