The Biggest Crypto Bug Bounties Ever Paid

By Owen Thurm Published November 6, 2026 5 min read

Quick answer. The largest crypto bug bounty we could confirm is $10 million, paid by Wormhole in 2022 to whitehat satya0x for an uninitialized proxy bug. Aurora's $6 million, Polygon's $2.2 million and Optimism's $2,000,042 come next.

Watch: The Biggest Crypto Bug Bounties Ever Paid 1:40

Video transcript

The largest crypto bug bounty ever confirmed was paid by Wormhole in 2022. Bigger headline numbers are usually offers, not payouts.

Wormhole paid ten million dollars to whitehat satya0x. A bridge implementation contract had been left uninitialized, and an attacker could have destroyed it. Wormhole fixed it the same day.

Aurora follows with six million in its own token for unlimited ETH minting. Then come Polygon, Optimism and Polygon again, each paying about two million.

This list counts only actual payouts, published by the protocol or Immunefi. Usual's sixteen million dollar program and Uniswap v4's fifteen and a half million are maximum offers.

The top five are bridges, chain-level contracts and a layer 2 client, holding pooled funds. Several paid their top Critical reward, and fixes often landed fast.

A bounty is priced against what a bug could take. In February 2022, an attacker netted three hundred twenty six million dollars from Wormhole through a different flaw.

Polygon submitted its fix two days after the report. A blackhat still took over eight hundred thousand MATIC first.

Guardian, which publishes this list, runs bounties through Vanguard. You put up fifty thousand dollars for Criticals and Guardian matches it. Defender contests and Managed Security handle the rest, from triage to fixes.

Read the full list, or talk to Guardian about giving researchers a reason to report to you.

Bug bounty headlines usually quote maximums. Usual's $16 million program on Sherlock and Uniswap v4's $15.5 million are offers, not payouts.

This list ranks what was actually paid, as published by the protocol or by Immunefi. Each entry says what the bug was and what was at risk.

The Ranked List

The date is the public write-up we cite. Payouts include co-funded bonuses paid for the same report.

#	Program	Payout	Write-up	The bug
1	Wormhole	$10,000,000	May 20, 2022	Uninitialized bridge implementation could be destroyed
2	Aurora	$6,000,000 in AURORA	Jun 7, 2022	Unlimited ETH minting in the Aurora Engine
3	Polygon	$2,200,000 in stablecoins	Dec 29, 2021	MRC20 transfers skipped balance checks
4	Optimism	$2,000,042	Mar 16, 2022	SELFDESTRUCT duplicated ETH balances
5	Polygon	$2,000,000	Oct 21, 2021	Plasma bridge exits could repeat
6	ArmorFi	1M ARMOR, about $1.5M	Feb 4, 2021	Claims could pay out far beyond coverage
7	Belt Finance	$1,050,000	Sep 30, 2021	A contract undercounted its own balance
8	Moonbeam	$1,050,000	Jul 28, 2022	Precompiles allowed DELEGATECALL impersonation
9	Notional	$1,000,000 plus 100,000 NOTE	Feb 2, 2022	Free collateral counted twice
10	Moonbeam, Astar, Acala	$1,000,000	Jan 4, 2023	Transfer values truncated to 128 bits

Belt's figure includes a $50,000 match from Priority One. Moonbeam's includes a $50,000 bonus from Moonwell.

What Each Bug Was

1. Wormhole: $10 million

satya0x reported the bug on February 24, 2022. A Wormhole bridge implementation contract had been left uninitialized after an earlier fix.

An attacker could set their own guardian set, then trigger an upgrade that self-destructed the implementation. Immunefi says that could have locked user funds; none were lost.

Wormhole fixed it the same day by initializing the contract. Our post on initializer vulnerabilities covers the bug class.

2. Aurora: $6 million

pwning.eth reported it on April 26, 2022. By using DELEGATECALL to reach Aurora's exit precompiles, an attacker could mint unlimited ETH in the Aurora Engine.

Aurora says more than 70,000 ETH, about $204 million, sat at risk in its bridge, plus pool liquidity. It paid its program maximum in AURORA tokens.

Aurora called it, to its knowledge, the second-highest bug bounty ever paid.

3. Polygon: $2.2 million

Leon Spacewalker reported it on December 3, 2021. Polygon's MRC20 transferWithSig accepted an invalid signature and skipped the balance check.

Anyone could have moved the contract's whole balance to themselves.

About 9.28 billion MATIC were at risk. Polygon submitted the fix on December 5, but a blackhat took 801,601 MATIC with the same bug first, per Immunefi.

4. Optimism: $2,000,042

Jay Freeman (saurik) reported it on February 2, 2022. In Optimism's l2geth, a self-destructing contract's balance went to the beneficiary and also stayed in place.

That duplicated ETH. Freeman writes that the listed bounty did not cover the bug, but Optimism said it would cover it equivalently and paid the full amount.

Boba, a fork with the same bug, later added $100,000.

5. Polygon: $2 million

Gerhard Wagner reported it on October 5, 2021. Polygon's Plasma bridge let an attacker exit the same burn transaction up to 223 times.

About $850 million was at risk. It was mitigated within one week, per Immunefi.

6 to 10

ArmorFi: a claim could withdraw 10^18 times the coverage bought, draining the underwriting contract.
Belt Finance: a logic error made a contract think it held less than it did. About $60 million in BNB was at risk.
Moonbeam: custom precompiles did not reject DELEGATECALL, so a contract could impersonate its caller.
Notional: a portfolio bitmap bug double-counted free collateral. The PoC drained 26.2 million DAI.
Moonbeam, Astar, Acala: Frontier cut EVM transfer values from 256 to 128 bits. About $200 million was at risk.

What the Payouts Share

Infrastructure: the top five are bridges, chain-level contracts and a layer 2 client.
Pooled funds: stated exposure runs from 26.2 million DAI at Notional to 9.28 billion MATIC at Polygon.
Maximums paid: Aurora, Optimism, Moonbeam and Notional paid their top Critical reward.
Tokens: Aurora paid in AURORA, ArmorFi mostly in vested tokens, and Notional added NOTE.
Fast fixes: Wormhole fixed its bug the day it was reported; Notional confirmed its bug in under an hour.
Repeat finders: pwning.eth appears three times, Alexander Schlindwein twice.

Most of the top ten date from 2021 and 2022. We found no larger confirmed payout since, though the largest offers have grown.

Bounties vs Exploit Losses

Wormhole shows the gap. On February 2, 2022, an attacker minted 120,000 wETH on Solana through a signature check flaw, netting $326 million, per Rekt.

Wormhole offered that attacker a $10 million bounty. Three weeks later, satya0x reported a different bug through Immunefi and was paid the same $10 million.

Polygon shows the race. Its MRC20 fix was submitted two days after the report, and a blackhat still took 801,601 MATIC first.

A bounty is priced against what a bug could take. Our bug bounty payout calculator shows how published programs size Critical rewards.

How This List Is Kept

Included: one payout for one report, published by the paying protocol or by Immunefi.
Values: as stated at the time. Token payouts use the value given then.
Bonuses: counted when paid by a partner for the same report.
Excluded: maximum offers, contest prize pools and payouts we could not confirm.
Last checked: November 6, 2026.

Many programs never publish payouts, so private awards could be larger. We update the list when a larger payout is published.

Choosing where to run a program? See our guide to web3 bug bounty platforms.

How Guardian Runs Bounties

With Vanguard, Guardian hosts and manages your bug bounty. You put up $50,000 for Criticals, and Guardian matches it.

After the audit, a public Defender contest opens the audited scope to researchers and AI auditors. Guardian funds its $100,000 Critical pot; the contest terms set the rules.

Under Managed Security, Guardian handles triage, impact validation and severity disputes, and drafts the fix.

For the protocol's side of a report, read how to triage a critical bug report.

Frequently Asked Questions

What is the largest bug bounty ever paid in crypto?

$10 million, paid by Wormhole to whitehat satya0x for a bug reported on February 24, 2022. Immunefi, which ran the program, called it a record. We found no larger confirmed payout as of November 2026.

Is a $16 million bug bounty bigger than Wormhole's?

Only as an offer. Usual's $16 million program on Sherlock, announced in April 2025, is a maximum for a Critical bug, per The Block. Wormhole's $10 million was actually paid.

Are crypto bug bounties paid in cash or tokens?

Both. Polygon paid $2.2 million in stablecoins. Aurora paid $6 million in AURORA tokens, ArmorFi paid mostly in vested tokens, and Notional added 100,000 NOTE to a $1 million award.

Why do bridges and layer 2s pay the most?

Their bugs put large pooled funds at risk. Aurora says more than 70,000 ETH sat at risk in its bridge, and Immunefi put Polygon's Plasma bridge exposure at about $850 million.

Sources

Give researchers a reason to report to you

With Vanguard, Guardian hosts your bug bounty, matches $50,000 on Criticals and funds a $100,000 Critical pot for a public contest.

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