Layer-1 blockchain halts network for 4 hours to stop $4.9 million hack, claims it was upgrade

On August 31, 2026, the Injective layer-1 blockchain paused block production for nearly four hours to deploy an emergency patch following a $4.9 million exploit. While the Injective Foundation claimed the network was "upgraded, not halted" and that user assets remained safe, researchers challenged this framing, pointing to a core-code vulnerability rather than isolated application issues. The incident temporarily jailed some validators and forced exchanges like Coinbase to restrict transfers.

Four-hour network halt

• ▪Injective validators deployed an emergency patch release v1.20.3-safeharbor.1 to resolve the exploit and resume block production on the network.
• ▪The Injective layer-1 blockchain paused block production for nearly four hours starting after block 181027005 at 16:09:59 UTC on August 31, 2026.

Core module vulnerability dispute

• ▪The emergency Injective software release v1.20.3-safeharbor.1 patched the core code by adding an insurance-fund denomination check and disabling binary-options settlement on the mainnet.
• ▪On-chain researcher Earthling Paddy stated the Injective exploit targeted native exchange and insurance modules, indicating the vulnerability existed in the blockchain's core protocol code rather than isolated ecosystem applications.

Validator jailing consequences

• ▪The jailing of Injective validators occurred as the accelerated network upgrade took longer than expected for validators and ecosystem infrastructure to deploy.
• ▪Some Injective validators were temporarily jailed after failing to apply the emergency software upgrade within the required timeframe on August 31, 2026.

Exchange transfer restrictions

• ▪The emergency response to the Injective exploit disrupted exchange transfers while successfully protecting consensus, native INJ, and staked assets.
• ▪Cryptocurrency exchanges Coinbase and Coins.ph temporarily restricted Injective token transfers during the network's emergency upgrade on August 31, 2026.

$4.9 million bridge exploit

• ▪According to researcher Earthling Paddy, the estimated $4.9 million in stolen funds remained unmoved in the attacker-linked wallet as of September 2, 2026.
• ▪Injective has not published a technical postmortem or disclosed the total losses, which party absorbed the shortfall, or how a replenished ecosystem pool was funded.
• ▪On-chain researchers estimate that attackers bridged approximately $4.9 million to the Ethereum network during the Injective exploit on August 31, 2026.

Foundation response controversy

• ▪On September 1, 2026, the Injective Foundation claimed the blockchain was upgraded rather than halted and that consensus, native INJ, and staked assets were never compromised.
• ▪Injective CEO Eric Chen stated on social media that Injective users were not affected by the exploit and that the team was assisting with recovery efforts.
• ▪On-chain researcher Earthling Paddy challenged the Injective Foundation's claim that the network did not halt and that the exploit was isolated to ecosystem applications.

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