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Reproduced Exploit

Predictable token address enables liquidity front-run — AuditVault synthetic reduction

This report describes a high-risk bug that allows an attacker to manipulate the deployment of a contract called DaosToken within the DaosLive contract. This predictability enables a front-running attack, which can result in a loss of protocol funds and a collapse in the token's value on Uniswap. Th…

Jan 2025•Other•access-control•3 min read

Chain

Other

Category

access-control

Date

Jan 2025

Source

AuditVault

PoC & write-upPoC for your local evm-hack-analyzerAuditVault PoCs

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Source & credit. Reproduction of a public audit finding curated by AuditVault — the original finding: 57870-h-03-predictable-token-deployment-address-enables-liquidity. Standalone Foundry PoC and full write-up: 57870-h-03-predictable-token-deployment-address-enables-liquidity_exp in the evm-hack-registry mirror.

Vulnerability classes: vuln/access-control/broken-logic · vuln/defi/sandwich-attack

Reproduction: self-contained Foundry PoC with an offline synthetic contract. Full trace: output.txt.

AuditVault finding: 57870 · [H-03] Predictable Token Deployment Address Enables Liquidity Pool Exploit in finalize()inDaosLive``

Key info#

ImpactHIGH — Predictable token address enables liquidity front-run
ProtocolDaoslive
FindingAuditVault #57870
Reporthttps://github.com/shieldify-security/audits-portfolio-md/blob/main/DaosLive-Security-Review.md
SourceAuditVault finding
Compiler^0.8.24 (synthetic reduction)
LossReduced invariant reproduced; no live funds moved
Attacker EOAConfigured synthetic caller
Attack contractExploit
Attack txLocal Foundry Exploit.attack() call
Chain · block · dateEthereum model · block 1 · synthetic
Vulnerable contractLocal synthetic vulnerable contract in test/
Bug classSee vulnerability-class tags above

TL;DR#

This report describes a high-risk bug that allows an attacker to manipulate the deployment of a contract called DaosToken within the DaosLive contract. This predictability enables a front-running attack, which can result in a loss of protocol funds and a collapse in the token's value on Uniswap. The bug has been fixed by using a more secure method called CREATE2 with a salt.

Background#

The upstream report is a Solidity finding. This page keeps the vulnerable statement and demonstrates its security consequence in a small, deterministic EVM model; no live RPC or external dependencies are required.

The vulnerable code#

SOLIDITY
// The exact vulnerable pattern is retained in test/57870-h-03-predictable-token-deployment-address-enables-liquidity.sol.
// @> see the marked statement in the synthetic reduction

Root cause#

The caller-controlled input or stale state is trusted before the required uniqueness, bounds, authorization, accounting, or reentrancy invariant is enforced. The marked line in the synthetic contract intentionally preserves that ordering so the assertion is executable.

Preconditions#

  • The vulnerable contract is deployed with the state described by the report.
  • The attacker can reach the affected entry point (or submit the report's crafted input).

Attack walkthrough#

  1. Exploit.run() initializes the minimal state from the report.
  2. The marked vulnerable operation executes without its required check.
  3. The contract records the resulting invariant violation and emits a Proof event.
  4. The test asserts the harm; the passing trace is recorded at output.txt:4.

Diagrams#

flowchart TD A[Attacker supplies crafted input] --> B[Vulnerable operation] B --> C{Missing invariant check} C --> D[Security impact demonstrated]
sequenceDiagram participant A as Attacker participant V as Vulnerable contract participant S as State A->>V: invoke affected entry point V->>S: apply unchecked update S-->>A: harm is observable

Remediation#

Apply the invariant before mutating state: accrue interest before adding principal; reject duplicate signers; use checked casts and bounded lengths; validate token/target/DAO identities; use nonReentrant; enforce slippage and fee equality; and validate the canonical authority or ownership relationship described by the report.

How to reproduce#

BASH
cd evm-hack-registry/57870-h-03-predictable-token-deployment-address-enables-liquidity_exp
forge test -vvvvv

The test is offline and uses only the shared forge-std library. The corresponding Playground bundle is generated from scripts/poc-configs/57870-h-03-predictable-token-deployment-address-enables-liquidity.mjs.

Sources#

Reference: https://github.com/shieldify-security/audits-portfolio-md/blob/main/DaosLive-Security-Review.md

Sources & further analysis#

Reproductions & code

Alerts & third-party analyses

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  • Solodit incident search: search.

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