Neutron governance takeover (Astroport, Drop) hack — September 2026

An attacker used Neutron's own on-chain governance to take over contracts belonging to protocols deployed on the chain on 22 September 2026. Neutron, a smart-contract chain in the Cosmos ecosystem, had entered what it called a long-term maintenance phase earlier in the year and had recently replaced its DAO-based governance with the Cosmos SDK's native governance module, which was allowed to change the admin of any contract and executed passed proposals immediately. Proposal 9, titled 'AIATO: AI Agent Takeover. Phase 1: Agent Admin Registration', contained eleven Update Admin messages that handed the attacker eight Astroport contracts, two Drop contracts and the Neutron investor vesting contract. According to the post-mortem published on 29 September by Solva, Neutron's security maintainer, a second wallet linked to the attacker spent 20,199 USDC on 31.6m NTRN and staked it eleven minutes before voting closed at 02:24 UTC; that stake made up 84.7% of the YES vote, and without it the proposal would not have reached quorum. Two earlier proposals with the same payload had failed: proposal 5 was rejected and proposal 7 was withdrawn in the face of heavy opposition. Between 02:38 and 03:04 UTC the attacker migrated ten of the contracts to its own code and withdrew their balances. The Astroport Treasury came under its control but was never drained.

The post-mortem puts the assets withdrawn at about $6.24m, valued at the prices recorded during the investigation, with ATOM at $1.75: 2.85m USDC, 1.72m ATOM, 803,955 DYDX, 95.2m NTRN, 370.3m ASTRO and small amounts of axlWETH and wstETH. It values the 1.59m dATOM taken from Drop at nothing, because the attacker also took the ATOM backing it and counting both would count the same ATOM twice. That total is the figure recorded here. Earlier estimates differed. Spaydh, a former Neutron contributor, put the initial impact at about $4.4m, which matches the post-mortem's count of what left Neutron over IBC before the chain was halted; the security tracker SlowMist recorded $9.3m and Protos $9.5m, and the higher figures are kept as the upper end of the range.

Neutron validators halted the chain at 07:43 UTC on 22 September. Part of the stolen ATOM had already reached the Cosmos Hub and was being sold through THORChain, so Hub validators halted their own chain at block 33,086,740 at 11:18 UTC. They restarted it at 12:00 UTC on 23 September on Gaia v28.3.0, with a one-time state change that moved the attacker's remaining 1,227,121 ATOM into a 4-of-6 validator multisig; the Hub stressed that it was not itself exploited and that no other balance was touched. Neutron resumed at 13:28 UTC on 25 September with a recovery release that restored all eleven contracts to their original code and admins, moved the assets that had never left the chain into a community-controlled recovery multisig, removed the purchased stake, locked both attacker accounts, froze new delegations and restricted governance to software upgrades and text proposals. Neutron's IBC rate limiter had kept 1.67m USDC and 14.09 axlWETH from leaving.

The sweeps did not catch everything. A THORChain refund of 168,990.9 ATOM reached the attacker's Hub address seven minutes after the restart and was sold on Osmosis for about 266,800 USDC. The post-mortem counts about $4.01m, 64% of the total, as secured: $1.86m that never left Neutron and $2.15m of ATOM on the Hub, both recorded here as recovered. The remaining $2.23m is lost: 1.18m USDC, about 496,000 ATOM sold through THORChain and Osmosis, the DYDX, the wstETH and 6 WETH. When the post-mortem was published the attacker's Ethereum collection wallet held 794.05 ETH and had sent nothing. The recovered funds sit in the two multisigs, whose signers will move them only after governance proposals on the Cosmos Hub and on Neutron authorise their return to users; the Neutron recovery team opened discussion of the Hub proposal on 30 September. No attribution has been published.