Hackers Exploit Software Bug to Steal $6 Million Across Six Cosmos Networks

Cosmos Labs said hackers exploited a vulnerability in the shared Cosmos EVM software layer, which affected more than 40 blockchains, to steal about 6 million dollars in assets from six networks in the ecosystem, including Mantra, TAC and KiiChain. According to the report, about 2.87 million dollars was drained through decentralized exchanges and another 2.85 million dollars through centralized exchanges, with the Mantra network suffering the largest loss after 720.9 million tokens were moved without authorization. Cosmos Labs confirmed it received the bug report on April 25, 2026, and patched it quietly in May, but said the public disclosure of technical details in August let hackers begin their attack within less than 12 hours. Following the incident, 13 of the 40 networks it contacted managed to pause activity or apply the fix before being exploited.