How much was lost in the Expanso hack?

The Expanso hack resulted in $88K in losses on November 27, 2023.

What attack technique was used in the Expanso exploit?

The Expanso exploit utilized Rugpull. 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.

Expanso Hack

TOTAL LOST $88K

Low Nov 27, 2023 Rugpull

Affected Chain 2023 Incident surface

Recovered - No recovery reported

All-Time Rank #1577 By amount stolen

Protocol Type Exit Scam/Rugpull Target category

Incident Overview

Quick Summary

The EXPSO token exit occurred on November 27, 2023, when scammers swapped 42.79 ETH from the LP liquidity pool.

Exploit Details

EXPSO is an ERC20 token traded on UniSwap. On November 27, 2023, the scammer removed liquidity from the LP pool, resulting in a total loss of 42.79 ETH. The stolen funds in the amount of $87,558 were transferred to another EOA through a contract created by the scammer.

Block Data Reference

Deployer Address:

https://etherscan.io/address/0x786F7F3a…f0A344

Scammer Address:

https://etherscan.io/address/0x95a6FcB5…79C180

Token Swap Transaction:

https://etherscan.io/tx/0x1245f63d…c10d60

Funds Holder as of Dec 4, 2023:

https://etherscan.io/address/0x50810f36…b05D9d

Malicious Contract Used by Scammer:

https://etherscan.io/address/0x8B544F47…eF8cca

Incident Report

Protocol / Project Expanso

Date of Incident November 27, 2023

Attack Technique Rugpull

Classification Token

Primary Source View Post-Mortem

Protocol Information

Protocol Type Exit Scam/Rugpull

Affected Token EXPSO

Official Website xpanse.trade/

Protocol Twitter/X @XpanseTrade

Team Anonymous

Source Code Verified On-Chain

Market Context at Time of Hack

Token Categories

Services DeFi Derivatives DAO Yield Farming Governance Synthetics BNB Chain Ecosystem

Protocol Links

GitHub Discord 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 rugpull 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 Expanso's contract logic - root cause: token

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? Hard to catch — private key / OpSec failures are outside smart contract audit scope

If you're auditing a protocol with similar architecture to Expanso, these are the critical security checks that could have prevented this incident (November 2023).

Verify all logic paths related to Rugpull 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/PeckShieldAlert/status/1728988361401196812

Threat Assessment

Severity Level

LOW

Attack Vector Rugpull
Root Cause Token
Year 2023

Learn to Prevent the Next Expanso

The Expanso 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