How much was lost in the Meter.io hack?

The Meter.io hack resulted in $4.4M in losses on February 06, 2022.

What attack technique was used in the Meter.io exploit?

The Meter.io exploit utilized Other. Understanding this attack vector is critical for smart contract auditors and developers building secure DeFi protocols.

How can developers prevent similar smart contract attacks?

Preventing smart contract hacks requires a combination of secure coding practices, thorough security audits, and understanding common attack vectors like reentrancy, oracle manipulation, and access control flaws. Smart Contract Hacking (SCH) provides hands-on training to help developers and auditors identify and prevent vulnerabilities before deployment.

Meter.io Hack

TOTAL LOST $4.4M

Medium Feb 06, 2022 Other

Affected Chain 2022 Incident surface

Recovered - No recovery reported

All-Time Rank #460 By amount stolen

Protocol Type Exploit/Other Target category

Incident Overview

The attacker's address:

https://etherscan.io/address/0x8d3d13ca…AF4D01

The attacker minted a substantial amount of BNB and WETH tokens, draining the bridge reserve of its BNB and wETH before all bridge transactions could be halted by Meter. This case also impacted the Hundred Finance on Moonriver.

Meter_io Passport is a fork of ChainSafe's ChainBridge, but with one change introduced to the deposit method of the ERC20 Handler.

The extended code had a wrong trust assumption which allowed the hacker to call the underlying ERC20 deposit function to fake a BNB or ETH transfer.

Exploit scenario:

- the Meter Bridge Contract provided by ChainSafe Systems has a vulnerability in deposit() function

- deposit() function doesn't check calldata "data" parameter to be matched with the message value in the function call

- this vulnerability allows anybody to call this function with fake deposit data and not be reverted

the attacker exploited this vulnerability and make a few deposits from the Ethereum network:

https://etherscan.io/tx/0xdfea6413…9e31f7

https://etherscan.io/tx/0x2d398796…0b629c

- the attacker exploited this vulnerability and made a few deposits from the BSC network:

https://bscscan.com/tx/0xc4d7e160…984950

https://bscscan.com/tx/0x63f37aff…f7ed8e

https://bscscan.com/tx/0xc7eb98e0…d8ffdc

- the attacker called swapOut() to withdraw a fake deposited amount from another chain:

https://moonriver.moonscan.io/tx/0xb3298f62…0d7050

- the attacker used AnySwap and cBridge to collect all funds in the Ethereum address

Stolen funds were deposited into Tornado Cash mixer on Ethereum:

https://bloxy.info/txs/transfers_from/0x8d3d13ca…af4d01?currency_id=1

Incident Report

Protocol / Project Meter.io

Date of Incident February 06, 2022

Attack Technique Other

Classification Other

Primary Source View Post-Mortem #1 View Post-Mortem #2 View Post-Mortem #3 View Post-Mortem #4

Protocol Information

Protocol Type Exploit/Other

Affected Token MTRG

Official Website meter.io/

Protocol Twitter/X @Meter_IO

Team Anonymous

Source Code Unverified

Market Context at Time of Hack

Token Categories

Hardware Marketplace VR/AR Gaming Metaverse BNB Chain Ecosystem

Protocol Links

GitHub Reddit

What the Attacker Needed to Succeed

Understanding the prerequisites for this type of attack helps auditors identify protocols that are most at risk and helps developers build better defenses.

Technical Knowledge Deep understanding of other and Solidity and EVM internals

Capital Required Seed capital to cover gas and initial position setup

On-Chain Access Ability to interact with smart contracts and deploy a custom exploit contract

Protocol Analysis Identification of the exploitable vulnerability in Meter.io's contract logic - root cause: other

Execution Speed Precise transaction ordering and timing to exploit the vulnerability within a single atomic block

Obfuscation Plan A strategy to launder and move stolen funds - typically through mixers, cross-chain bridges, or decentralized DEX swaps to resist tracing

What Auditors Should Check

Could this have been caught in audit? Likely — with a thorough Other audit checklist and test coverage

If you're auditing a protocol with similar architecture to Meter.io, these are the critical security checks that could have prevented this incident (February 2022).

Verify all logic paths related to Other are guarded by proper access controls and input validation
Review privileged functions (owner, admin, governance) for potential abuse vectors - centralization risks should be documented and bounded with timelocks or multi-sigs

Master these auditing techniques with hands-on labs and real exploit scenarios in the Smart Contract Hacking course.

Free Trial

Sources & References

01
Source 1 https://twitter.com/Meter_IO/status/1490103308421255168
02
Source 2 https://twitter.com/ishwinder/status/1490227406824685569
03
Source 3 https://rekt.news/meter-rekt/
04
Source 4 https://twitter.com/peckshield/status/1490121762847092736

Threat Assessment

Severity Level

MEDIUM

Attack Vector Other
Root Cause Other
Year 2022

Learn to Prevent the Next Meter.io

The Meter.io hack is one of many attacks that skilled auditors are trained to detect before deployment. Master real exploit patterns and defense techniques with hands-on Web3 security training.

Start Free Trial Browse Attack Library