link.png

ID:

bitbtc-1262

Date:

Status:

Incident Count:

October 18, 2022

Near-Miss

1

info.png
target.png
REKT

Contributor:

chain.png

web3rekt.com

KYC By:

KYC:

None

info.png

Audit By:

Audits:

None

Loss Amount:

-

info.png

Recovered:

-

Rewards:

Ticker:

USD, BitBTC

info.png

The Optimism bridge supporting privacy coin BitBTC is actively being exploited for 200 billion BitBTC tokens. Luckily it was patched before any reported loss.

The BitBTC Protocol is to solve the problems of high price of BTC and slow transfer speed,1BTC = 1 million BitBTC.

Specifically, the BitBTC bride contained a “critical exploit” that left it “trivially vulnerable.” It involves the bridge’s relationship between Ethereum’s layer 1 (L1) addresses and Optimism’s layer 2 (L2) addresses.

The Optimism L2 side of the bridge lets you withdraw any token, and it lets that token pick the L1Token address passed to the L1 side of the bridge. However, the L1 bridge completely ignores what the L2 token was, and just goes ahead and mints the arbitrary L1 token! That means an attacker could deploy their own token on Optimism, give themselves all the supply, and set that token's l1Token to the real BitBTC L1 address.

Then, when the attacker withdraws their malicious token through the BitBTC bridge, it gives them real BitBTC tokens on L1! Luckily, this exploit would take 7 days to go through, during which the L1 bridge could be fixed via an upgrade.

info.png

DISCLAIMER: While web3rekt has used the best efforts in aggregating and maintaining this database, this web site makes no representations or warranties with respect to the accuracy or completeness of its information and data herein, and specifically disclaim any implied warranties of merchantability or fitness for any particular purpose. 

Under no circumstances, shall web3rekt be liable for any loss of profit or funds, any regulatory or governmental penalties, any legal costs, or any other commercial and non-commercial damages, including but not limited to special, incidental, consequential, or other damages from any or all usage of the data and information derived from this database.