Heimdall

Heimdall: the exit guard for Arbitrum depositors

The problem

In 2026, 17 confirmed hacks hit Arbitrum projects, and a further $24M exploit hit AFX Trade. Around $50 million was lost in total. The losses fell on the people who had put money in: vault depositors, lenders and liquidity providers.

Smaller teams were hit hardest. 16 of the 17 hacks took less than $2M each, which is enough to break a small protocol. TMX drained for about 36 hours with no emergency pause, and the team stayed silent for days. Cascade froze withdrawals after analysts had warned users to leave about 10 days earlier. At Ostium, the largest vault loss, 3,666 wallets were affected, and the first repayment pool covers about 2.7% of the $23.75M lost.

Most depositors weren't watching. Even those who noticed couldn't all get out, because when everyone rushes to withdraw, a vault pays the first ones out and the rest take the loss. Existing protection serves funds and vault managers, not everyday depositors.

The solution

Heimdall gives every depositor their own guard. You move your Morpho or Aave position into a small contract that only you own. Heimdall watches the protocol every block for six warning signs: fast outflows, a falling share price, a wrong oracle price, a stablecoin losing its peg, drying liquidity and risky admin changes. At Critical it exits automatically and sends the money to your wallet, paying a priority fee to get out early. If the vault can only pay part of it, Heimdall takes what is available and retries every block until you are out. Telegram and email alerts never delay an exit.

Why it works this way

One-way by design. Exits are hard-coded to pay the owner. The automated keeper can only trigger an exit, never move funds elsewhere. You can pause it, turn it off or withdraw yourself at any time.

Your own guard, not a shared pool. Nobody else's position or mistake can touch your funds.

Built for the race. Alerts alone leave people stuck. Heimdall exits early and keeps retrying.

What was verified

Real exits on real protocols. On a fork of Arbitrum One, Heimdall withdrew 4,999.999998 of 5,000 USDC from Aave V3 and 9,999.999998 of 10,000 USDC from the Morpho Gauntlet USDC Core vault, all paid to the owner.

Recreated attacks. We recreated the attack patterns behind this year's hacks (a fast drain, oracle tampering and a stablecoin depeg) on a fork of Arbitrum One with the real Morpho vault. In each one, Heimdall caught the warning signs, escalated to Critical and exited, first partially and then in full. A matching unprotected position was left stuck.

Deployed. The contracts are live and verified on Arbitrum Sepolia, marked "Pass - Verified" on Arbiscan (factory 0x3346D96f88122eC3c7B50E50120789ECA21bdcf6).

Why this matters

These are not one-off accidents. Two patterns explain most of this year's Arbitrum losses:

Leaked or stolen admin keys: Ostium, Stake DAO, USDGambit and AFX, over $40 million together.

Price or oracle manipulation: Rocket, Cascade, SEA and Silo.

Both keep repeating across the industry. CertiK counted 344 incidents in the first half of 2026, with compromised keys the costliest type at $444 million. It also found attackers increasingly target contracts more than a year old. That matches Arbitrum: IPOR's drained vault was 490 days old, and Stake DAO's deployer had kept owner rights for 27 months. Price manipulation drained Venus on BNB Chain in March through repeated borrow cycles, after an audit had flagged the weakness.

On Arbitrum, 94 lending protocols hold about $794 million and 101 yield protocols about $502 million. Outside the five largest lenders, 89 smaller lending protocols hold around $10 million between them, and that size of team is where most of this year's hacks landed.

At TMX there were 36 hours to leave, and at Cascade there were ten days of public warnings. The money was lost because no one was watching on the depositors' behalf.

Heimdall gives every depositor that watch, and gets them out