ChainBleedv0.1 · open intel
← back to feed·ETHFRONTEND2023-09-19 · 2y ago
Incident · DEFILLAMA

Balancer V2

Frontend Attack
Estimated loss
$238.0K
VERDICT —OUT OF SCOPE
Root cause is a frontend / UI hijack — users authorized the malicious transaction from a compromised site or DNS. On-chain contract was not the failure surface; pre-deployment audit cannot catch this class.
▰ METHOD
Frontend Attack
FRONTEND
Root cause

Root-cause analysis not yet published. The incident description below contains all currently available signal — review the attack transaction directly for definitive forensics.

▰ PROOF OF CONCEPT
DEFIHACKLABS
src/test/2023-08/Balancer_exp.sol
view forked test on github ↗

Reproducible Foundry test fork from SunWeb3Sec/DeFiHackLabs. Clone the repo, run forge test against the file path above, and replay the exploit against a mainnet fork at the historical block. Use for reproduction only — not for live targets.

Forensic narrative

Classification: Protocol Logic. Technique: Frontend Attack. Target type: DeFi Protocol. Affected chains: Ethereum.

Sourced from
DefiLlama Hacks dataset · api.llama.fi/hacks
Technical record
chain
ethereum
protocol
Balancer V2
bug_class
frontend
date_occurred
2023-09-19
loss_usd
$238,000
classification
Protocol Logic
technique
Frontend Attack
target_type
DeFi Protocol
source_id
dl:2611
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