Shibarium, the Layer 2 blockchain tied to Shiba Inu, has resumed operations following a multi-million-dollar exploit that forced developers to halt activity and initiate a 10-day emergency response.
The attack targeted the network’s bridge to Ethereum, exposing validator controls and draining millions of dollars in assets before developers regained control.
The breach unfolded when a malicious actor borrowed 4.6 million BONE, Shibarium’s governance token, through a flash loan.
By temporarily amplifying their stake, the attacker was able to control 10 of the 12 validator keys, surpassing the two-thirds consensus threshold needed to push fraudulent checkpoints to Heimdall, Shibarium’s consensus layer.
Shibarium Restores Security After $2.4M Exploit, Implements Long-Term Safeguards
With that leverage, the attacker drained approximately 224.57 ETH and 92.6 billion SHIB tokens from the bridge contract, worth around $2.4 million at the time.
An additional $700,000 in KNINE tokens from K9 Finance was impacted. K9 Finance’s DAO responded by blacklisting the attacker’s wallet, rendering the stolen KNINE unsellable.
Shiba Inu’s Layer 2 network, @ShibariumNet, came under fire after a coordinated flash loan attack exploited its bridge, draining $3 million.#Shib #Shibariumhttps://t.co/uj6EytOsgQ
— Cryptonews.com (@cryptonews) September 14, 2025
Developers immediately froze staking and unstaking functions across the network to prevent further outflows. Because the borrowed BONE was subject to a withdrawal delay, the attacker was blocked from fully exiting their validator position, giving Shibarium’s core team time to isolate the threat.
Shiba Inu developer Kaal Dhairya described the exploit as “sophisticated” and said it had likely been prepared for months. He confirmed that law enforcement had been contacted and that security firms, including Hexens, Seal 911, and PeckShield, had been brought in to investigate.
Over the past 10 days, the Shibarium team and external partners have worked continuously to contain the breach and restore the network.
In a detailed update, developers said ownership of more than 100 key contracts spanning Shibarium, ShibaSwap, and related projects had been migrated to hardware-secured custody with multi-party controls.
All validator signer keys were rotated to cut off exposure from the compromised state, while new blacklisting mechanisms were added to staking flows. These measures allow developers to block any address identified as malicious from staking, unstaking, or withdrawing rewards.
A key step in the recovery involved neutralizing the 4.6 million BONE delegation tied to the attacker. Developers introduced a contract upgrade to rescue the tokens, cleaning up legacy staking data and removing the malicious delegation from the ledger.
Shibarium Update – Quick Recap
What happened
•An attacker injected fake checkpoints and tried to take control using a huge 4.6M BONE stake.
•Heimdall (the chain checkpoint system) halted to protect funds.
•Worked non-stop for 10+ days with Hexens… pic.twitter.com/3fTjOfR4y0— Shibarium | SHIB.IO (@Shibizens) October 3, 2025
The fix was first tested on Shibarium’s Devnet and Puppynet before being applied to mainnet, with Hexens reviewing the process.
To further reduce risk, the withdrawal delay for staking was increased from one checkpoint to around 30, giving developers more time to detect anomalies before funds can be moved.
The exploit also disrupted Shibarium’s checkpointing process. By injecting three fake checkpoints into the Root Chain Manager contract on Ethereum, the attacker caused Heimdall to halt, preventing legitimate checkpoints from being posted.
Shibarium Developers Resume Checkpointing, Outline Post-Hack Roadmap
Developers corrected the issue by adjusting the on-chain pointer to the last valid checkpoint, using a built-in housekeeping function. After a three-stage validation across test networks and mainnet, checkpointing resumed normally.
The decision not to offer the attacker a bounty contract was also explained. Developers said no response was received to the initial outreach and that on-chain evidence showed the attacker was moving stolen funds.
They argued that deploying a bounty contract would have added unnecessary complexity without benefit, so they kept their focus on securing the protocol and restoring integrity.
Looking ahead, Shibarium developers outlined several near-term priorities. Work is underway to add blacklisting controls to the Plasma Bridge, which was paused following the hack.
The team also plans to re-initiate the bridge with phased safeguards and said a mechanism to make affected users whole will be introduced once it can be done securely. Details of the refund plan will be released at a later date.
Technical improvements are also being rolled out. Shibarium has partnered with dRPC.org to expand infrastructure access and has consolidated its official RPC endpoint at rpc.shibarium.shib.io.
Also, documentation for node operators is being overhauled to simplify setup, while new monitoring and playbooks have been developed to detect checkpoint mismatches and key rotations more effectively.
The incident marks one of the largest attacks on Shibarium since its launch, showing the risks of validator manipulation in proof-of-stake systems. Despite the breach, Shiba Inu’s SHIB token has risen 7.3% in the past week, trading at $0.00001268.
It remains 85% below its all-time high of $0.00008616 reached in 2021. BONE, meanwhile, briefly spiked from $0.165 to $0.294 in the immediate aftermath of the attack before stabilizing near $0.202.
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