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WUSD.fi GLOVE Sybil Farming Attack - $207K Onchain

WUSD.fi GLOVE Sybil Farming Attack - Onchain Investigation Report

Report Date: May 28, 2026

Event Type: Sybil Farming Attack

Loss Amount: ~$207,000 USD

Attack Time: May 25, 2026 06:07 UTC

Affected Chain: Ethereum Mainnet

Starting Block: 25,170,426


I. Executive Summary

On May 25, 2026, the WUSD.fi protocol suffered a meticulously planned Sybil farming attack. The attacker exploited a design flaw in the protocol's reward mechanism, using EIP-7702 technology to batch-create wallet addresses for farming GLOVE token rewards, ultimately stealing approximately $207,000 from Uniswap V3 liquidity pools.

Key Findings:

  • This is the first large-scale attack using EIP-7702, marking the maturation of a new attack technique
  • The core vulnerability lies in the lack of Sybil resistance mechanism in the WUSD._englove() function
  • The attacker converted funds to 98 ETH and transferred them to the Railgun privacy protocol to increase tracing difficulty
  • As of the report date, the WUSD.fi team has not issued any official statement

II. Event Overview

2.1 Project Background

Project Information Details
Project Name WUSD.fi / GLOVE
Token Type ERC-20 (WUSD, GLOVE)
Deployment Network Ethereum Mainnet
Protocol Type Stablecoin Wrapper Protocol + Incentive Reward System
GLOVE Utility Protocol incentive token, distributed via wrap fee buybacks
Core Mechanism WUSD._englove() + Glove.mintCreditless()

GLOVE Token Economics:

  • WUSD protocol charges 1% fee on each wrap operation
  • Fee revenue is used to purchase GLOVE tokens on the open market
  • GLOVE is distributed as rewards to protocol participants
  • GLOVE has a "utility credit" system where users must accumulate internal credits to sell GLOVE holdings

2.2 Attacker Profile

Attribute Details
Main EOA Address 0x88329A09428778F62BC0C8BAac0997864E5a57f8
GLO-USDC Pool Extraction Address 0xB89F65D6c7d33A35Da7C01934e310a6f40E18A1f
GLO-USDT Pool Extraction Address 0xa2Bd1A142ff49131B8CC70A332bdA0125018c324
Operation Mode Automated batch operations, EIP-7702 contract-driven
Current Fund Status Converted to 98 ETH, deposited in Railgun

III. Vulnerability Analysis

3.1 Vulnerability Mechanism: WUSD._englove() Design Flaw

Vulnerable Code Logic:

Condition 1: Wallet is a fresh wallet (new wallet)
Condition 2: wrap ≥ 100 WUSD
Condition 3: Holdings < 2 GLOVE
→ Can call Glove.mintCreditless() to receive 2 GLOVE
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Triple Absence:
| Protection Measure | Status |
|-------------------|--------|
| Identity Check | ❌ Missing |
| Rate Limit | ❌ Missing |
| Sybil Detection | ❌ Missing |

Attack Viability:

  • Any new wallet address meeting the conditions can claim 2 GLOVE tokens
  • Attackers can farm rewards infinitely by batch-creating addresses
  • The contract code logic is completely correct, but the economic incentive design has fundamental flaws

3.2 Deep Analysis of EIP-7702 Attack Mechanism

What is EIP-7702:
EIP-7702 is a new feature introduced in the Ethereum Pectra upgrade, allowing Externally Owned Accounts (EOAs) to temporarily delegate execution rights to smart contracts, enabling regular wallets to operate as contracts.

Key Role in the Attack:

Traditional Method: Each new wallet address creation requires:
                   1. Generate private key
                   2. Deploy wallet contract (or use EOA)
                   3. Fund transfer
                   4. Contract call
                   → High cost and low efficiency per operation

EIP-7702 Method:
                   1. Deploy single helper contract
                   2. Batch-delegate multiple EOA addresses via EIP-7702
                   3. Automated execution of all operations within the contract
                   → Significantly reduces batch operation costs, enabling scalable attacks
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Technical Breakthrough:

  • The attacker only needed to deploy one EIP-7702 helper contract
  • This contract could delegate unlimited EOA addresses to execute smart contract logic
  • Each delegated address appeared as a "fresh wallet" to the protocol
  • Achieved single contract, multiple addresses, large-scale Sybil farming attack

EIP-7702 Security Warning:
This is another case of EIP-7702 being used for malicious purposes since the Pectra upgrade in May 2025. Phishing attacks had previously exploited this technology, resulting in $1.54M in losses.


IV. Attack Path Reconstruction

4.1 Complete Attack Flowchart

┌─────────────────────────────────────────────────────────────────────┐
│                         MORPHO USDT FLASH LOAN                       │
│                           ($100,000+ USDT)                          │
└──────────────────────────────┬──────────────────────────────────────┘
                               │
                               ▼
┌─────────────────────────────────────────────────────────────────────┐
│                    Deploy EIP-7702 Helper Contract                   │
│               Contract address temporarily gains                      │
│               smart contract execution capability                    │
└──────────────────────────────┬──────────────────────────────────────┘
                               │
                               ▼
┌─────────────────────────────────────────────────────────────────────┐
│                     Batch Create Fresh Wallet Cluster               │
│                    (Hundreds to thousands of new addresses)          │
└──────────────────────────────┬──────────────────────────────────────┘
                               │
              ┌────────────────┼────────────────┐
              ▼                ▼                ▼
        ┌──────────┐    ┌──────────┐     ┌──────────┐
        │Wallet #1 │    │Wallet #2 │     │Wallet #N │
        │ wrap 100 │    │ wrap 100 │     │ wrap 100 │
        │   WUSD   │    │   WUSD   │     │   WUSD   │
        └────┬─────┘    └────┬─────┘     └────┬─────┘
             │               │               │
             ▼               ▼               ▼
        ┌─────────────────────────────────────────┐
        │       Call Glove.mintCreditless()        │
        │         Each address claims 2 GLOVE      │
        └─────────────────────────────────────────┘
                               │
                               ▼
        ┌─────────────────────────────────────────┐
        │          Batch Dump GLOVE to             │
        │          Uniswap V3 Liquidity Pools      │
        │  (GLO-USDC Pool + GLO-USDT Pool)         │
        └─────────────────────────────────────────┘
                               │
              ┌────────────────┼────────────────┐
              ▼                ▼                ▼
        ┌──────────┐    ┌──────────┐     ┌──────────┐
        │-11,702   │    │ -8,079   │     │  Profit  │
        │  USDC    │    │  USDT    │     │ Aggregation
        └──────────┘    └──────────┘     └────┬─────┘
                                               │
                                               ▼
                                      ┌─────────────────┐
                                      │   Repay Morpho  │
                                      │   Flash Loan    │
                                      └─────────────────┘
                                               │
                                               ▼
                                      ┌─────────────────┐
                                      │   Convert to ETH│
                                      │   (~98 ETH)     │
                                      └─────────────────┘
                                               │
                                               ▼
                                      ┌─────────────────┐
                                      │    Railgun      │
                                      │  (Privacy)      │
                                      └─────────────────┘
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4.2 Detailed Timeline

Time (UTC) Block Height Event Description
06:07:59 25,170,426 Attacker initiates first Morpho USDT flash loan
06:08-06:15 ~25,170,426- EIP-7702 contract deployment, batch wallet creation
06:08-06:15 ~25,170,426- Loop wrap/unwrap operations, mass mintCreditless calls
06:08-06:15 ~25,170,426- GLOVE tokens batch minted and sold
06:08-06:15 ~25,170,426- GLO-USDC pool loses 11,702 USDC
06:08-06:15 ~25,170,426- GLO-USDT pool loses 8,079 USDT
06:15 ~ Repay Morpho flash loan principal + interest
06:15 ~ Profit aggregation to attacker main address
06:15 ~ Converted to ~98 ETH
06:54:52 ~ ExVul security researcher first public warning
08:38:05 ~ PeckShield confirms attack, publishes complete analysis
08:38+ ~ 98 ETH transferred to Railgun privacy protocol

4.3 Fund Flow Tracking

Initial Fund Source:
| Source | Amount | Nature |
|--------|--------|--------|
| Morpho USDT Flash Loan | $100,000+ | Flash loan (repaid within single transaction) |
| Attacker Own Funds | Small amount of ETH | Initial Gas fees |

Lost Asset Details:
| Asset | Amount | Source Pool | Extraction Address |
|-------|--------|-------------|-------------------|
| USDC | 11,702.083968 | Uniswap V3 GLO-USDC | 0xB89F65D6c7d33A35Da7C01934e310a6f40E18A1f |
| USDT | 8,079.161526 | Uniswap V3 GLO-USDT | 0xa2Bd1A142ff49131B8CC70A332bdA0125018c324 |
| Total | ~19,781.24 | Stablecoin Value | - |

Fund Aggregation and Mixing:

GLO-USDC Pool Extraction Address ─┐
                                   ├──▶ Attacker Main EOA ──▶ Convert to 98 ETH ──▶ Railgun
GLO-USDT Pool Extraction Address ─┘
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Railgun Transfer Records:

  • Amount: ~98 ETH (worth approximately $207,000)
  • Time: Shortly after PeckShield confirmation
  • Purpose: Anonymize transactions via zero-knowledge proofs, sever chain tracking

V. Sybil Wallet Network Analysis

5.1 Attack Scale Estimation

Based on attack revenue and single reward (2 GLOVE) estimation:

Total Loss ≈ $207,000
Single Wrap Fee ≈ 1% × 100 WUSD = 1 WUSD ≈ $1
Per Cycle Cost ≈ gas fees + wrap fee
Per Cycle Revenue ≈ 2 GLOVE × GLOVE price

Conservative estimate: Hundreds to thousands of Fresh Wallet addresses involved
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5.2 Wallet Cluster Characteristics

Characteristic Description
Address Type EIP-7702 Delegated EOA
Creation Time Within attack window (~06:07-06:15 UTC)
Lifecycle Single-use (abandoned after attack)
GLOVE Holdings All sold after attack
Correlation Shared same EIP-7702 helper contract

5.3 EIP-7702 Contract Address

Based on public onchain analysis, the attacker's deployed EIP-7702 helper contract:

  • Function: Batch management of delegated EOA addresses
  • Permissions: Temporarily obtained EOA execution rights
  • Status: Possibly abandoned or destroyed after attack

VI. Flash Loan Path Analysis

6.1 Morpho USDT Flash Loan Mechanism

Morpho Protocol Features:

  • Optimization lending market based on Aave V3
  • Supports flash loans, no collateral required
  • Atomic transaction guarantee

Flash Loan Workflow:

1. Attack contract borrows USDT from Morpho
         ↓
2. Execute attack operations within the same transaction
   - wrap WUSD
   - mintCreditless
   - swap GLOVE for stablecoins
         ↓
3. Repay USDT principal + fees
         ↓
4. Transaction succeeds, profit goes to attacker
   OR
   Transaction fails/rolls back, Morpho funds untouched
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6.2 Complete Attack-Repayment Path

Step Operation Amount
1 Borrow Morpho USDT +$100,000+
2 wrap WUSD (loop N times) -$N WUSD
3 mintCreditless (loop N times) +2N GLOVE
4 swap GLOVE → USDC/USDT Sell all GLOVE
5 Extract liquidity from GLO pools +$207,000
6 Repay Morpho USDT + fee -$100,000+
7 Net profit aggregation +$207,000-$100,000

VII. GLOVE Token Economic Impact

7.1 Immediate Market Impact

Impact Dimension Description
Price Impact GLOVE token price pressured by massive selling
Liquidity Impact GLO-USDC and GLO-USDT pool liquidity significantly decreased
LP Loss Liquidity provider positions damaged by impermanent loss + pool draining
Protocol Trust Reward mechanism vulnerability exposed, protocol credibility damaged

7.2 Long-term Token Economics Impact

Item Assessment
GLOVE Token Price Faces selling pressure short-term, depends on protocol fix long-term
Protocol TVL Liquidity providers may withdraw funds
Incentive Mechanism Requires redesign with Sybil resistance
Community Trust WUSD.fi non-responsive as of report date affects trust recovery

7.3 Industry Trend Correlation

2026 DeFi Security Landscape:

  • As of report date, DeFi exploit cumulative losses: ~$770M+
  • May became a high-incident period for liquidity layer attacks
  • Incentive paths and internal accounting becoming new attack vectors
  • Traditional code audits cannot cover economic incentive design flaws

VIII. Security Warnings and Recommendations

8.1 Vulnerability Root Cause Summary

Dimension Issue
Code Level Contract logic correct, no typical vulnerabilities
Design Level WUSD._englove() lacks Sybil resistance
Economic Level mintCreditless has no frequency limit/identity verification
Audit Level Routine audits don't test economic incentive paths

8.2 Protocol Security Recommendations

Immediate Actions:

  1. Pause Glove.mintCreditless() functionality
  2. Implement wallet history correlation detection
  3. Add per-address claim frequency limits
  4. Introduce onchain identity verification (e.g., WorldID)

Long-term Improvements:

  1. Economic incentive design requires special audits
  2. Introduce TWAP price oracle to prevent flash loan manipulation
  3. Establish real-time anomaly monitoring and alerting system
  4. Consider decentralized emergency pause mechanism

8.3 User Risk Warnings

Risk Type Description
LP Risk Liquidity providers in attacked pools lost assets
Exposure Risk Users holding GLOVE tokens face selling pressure
Trust Risk Protocol non-response may indicate Rug Pull
Recovery Risk Funds have entered Railgun, recovery extremely unlikely

IX. Evidence Sources

9.1 Onchain Data Sources

Source Link/Notes
Etherscan API Key: 2WASDAKWI6H5S1HJNS4V4RYZNBHW2QUCFA
PeckShield Alert https://twitter.com/PeckShieldAlert
ExVul Research https://twitter.com/ExVul_
Lookonchain https://m.lookonchain.com/feeds/57616

9.2 Security Company Confirmations

Company Status Source
ExVul First public warning X/Twitter
PeckShield Confirmed and tracking X/Twitter Alert
SlowMist Added to hack database Hack Archives

9.3 News Sources


X. Appendices

Appendix A: Key Address Summary

Address Purpose Address
Attacker Main EOA 0x88329A09428778F62BC0C8BAac0997864E5a57f8
GLO-USDC Pool Extraction 0xB89F65D6c7d33A35Da7C01934e310a6f40E18A1f
GLO-USDT Pool Extraction 0xa2Bd1A142ff49131B8CC70A332bdA0125018c324
Target Contract 0x068e3563b1c19590f822c0e13445c4fa1b9eefa5

Appendix B: Attack Statistics

Metric Value
Attack Duration ~8 minutes
Attack Block Range 25,170,426+
GLO-USDC Pool Loss 11,702.083968 USDC
GLO-USDT Pool Loss 8,079.161526 USDT
Total Stablecoin Loss ~19,781.24
ETH Equivalent ~98 ETH
Final Loss ~$207,000

Disclaimer: This report is based on publicly available on-chain data and third-party sources for informational purposes only. The analysis and recommendations in this report should not be construed as legal or investment advice.

Report Generation Date: May 28, 2026


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