Cosmos Labs, a leading layer-0 blockchain stack, has issued an urgent warning to blockchain networks after a security vulnerability in its EVM infrastructure was exploited, triggering emergency halts. The incident has already affected KiiChain, MANTRA, and some others. This incident highlights the risks tied to multiple networks depending on shared blockchain software.
As investigations proceed, developers are under pressure to safeguard users while rebuilding confidence in the broader Cosmos ecosystem.
Shared EVM Vulnerability Triggers Emergency Response
The latest incident is particularly significant because Cosmos EVM technology is used across multiple blockchain projects, creating a shared security dependency. KiiChain, a layer-1 blockchain for stablecoins and RWAs, confirmed that its recent security incident stemmed from a vulnerability in the Cosmos EVM module, rather than its own application code.
Attackers exploited the weakness repeatedly, moving assets away from KiiChain through Hyperlane before the network was halted. According to KiiChain, the immediate response focused on containing the attack, tracing transactions, and preventing additional losses while technical teams investigated.
The network remains halted as developers work toward remediation and prepare a detailed incident report for affected users. Meanwhile, reports indicate that approximately 148 million KII was stolen across multiple transactions before the chain was stopped.
Cosmos Vulnerability Hits MANTRA Chain
While KiiChain’s breach appears to have produced the more direct financial impact, MANTRA, an EVM-compatible layer-1 blockchain for real-world assets (RWA), saw its market price drop by more than 11% following a similar security incident. In response, the network immediately froze transactions, deposits, withdrawals, and other operations while its engineering and security teams investigated the breach.
MANTRA later said the incident was contained and isolated to its Cosmos EVM module, adding that user funds were not exploited. The project subsequently began testing a patched version before restoring normal operations.
Earlier, a vulnerability in the Cosmos EVM was revealed in March. The issue involved problems with how the system handled states during nested EVM execution. This led to losses worth about $7 million on Saga EVM.
These incidents highlight a challenging reality— while blockchain networks may seem independent, they often depend on shared technical foundations. Users are now waiting for further instructions while developers work on a safe way to restart the halted networks.
Chris Lion | August 26, 2026
