KiiChain, TAC, and other Cosmos-based blockchains exploited after "negligent" vulnerability disclosure

Multiple blockchains based on the Cosmos chain suffered exploits after Cosmos Labs publicly disclosed a vulnerability in the Cosmos EVM. Some have criticized Cosmos for "negligence" in their vulnerability management. KiiChain, one of the affected chains, wrote in their postmortem, "This loss was avoidable. ... Publishing a security fix in the open, before the chains running that code have been told privately and given time to patch, hands the vulnerability to anyone reading the commit. Standard responsible disclosure exists precisely to prevent this. Cosmos Labs gave no advance notice to downstream chains, did not flag the release as security critical, and did not tell affected chains that a public release had happened until Friday 21 August, two days later."KiiChain was exploited for around 148 million KII, which the attacker was able to cash out for around $1.6 million. TAC, a Telegram-focused blockchain, was exploited for about 3 billion TAC (~$7.5 million). Nesa Chain was…