Incident case

Rainbow Bridge August 2022 fabricated-block attack attempt

An attacker submitted a fabricated NEAR block to the Rainbow Bridge contract with a 5 ETH safe deposit. Automated watchdogs challenged the transaction in under approximately 31 seconds; no user funds were reported lost and the attacker forfeited the deposit.

reviewedcurrent

Incident facts

Incident title
Rainbow Bridge August 2022 fabricated-block attack attempt
Bridge
Rainbow Bridge
Incident date
2022-08-20
Incident type
Attempted Exploit
Major incident
Yes
Affected chains
Ethereum, NEAR
Affected assets
ETH, Unknown
Attack category
Fabricated Light Client Block
Reported loss
No user-fund loss reported
Amount confidence
High
Loss amount basis
Contemporaneous Reporting Quoting The Aurora Labs CEO
Recovery
Not Required
Reimbursement
Not Applicable
Restart
Not Interrupted
Current outcome
Attack Thwarted
Postmortem
Partial
Resolution
Final outcome known
Last reviewed
2026-06-15
Last verified
2026-06-15

Amount and valuation

The fabricated-block attempt was challenged before bridge funds were released. The attacker lost a 5 ETH safe deposit.

The attacker's forfeited 5 ETH deposit is recorded separately and is not bridge or user loss.

Timeline events

  • August fabricated-block attempt blocked automatically2022-08-20

    Watchdogs challenged a fabricated NEAR block in under approximately 31 seconds; the attacker forfeited a 5 ETH safe deposit.

    Fabricated Block Automatically ChallengedHigh

    The deposit loss belongs to the attacker, not users or bridge reserves.

Evidence records

Source tiers describe evidence authority, not certainty for every claim. Tier 1 is the strongest source class; Tier 2 and Tier 3 provide progressively more secondary or supporting context. Source notes define what each record actually supports.

Known unknowns

Independent incident archive

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