Twitter user saves cross-chain bridge from potential exploit
A cross-chain bridge between BitBTC and the Ethereum layer-2 community Optimism has been capable of keep away from a probably expensive exploit due to the work of an eagle-eyed Twitter person.
The customized cross-chain bridge affords a ramp for customers to ship belongings between Optimism’s community and BitAnt’s decentralized finance (DeFi) ecosystem, which incorporates yield companies, nonfungible tokens (NFTs), swaps and the BitBTC token, during which 1 million BitBTC represents 1 Bitcoin (BTC).
The BitBTC bridge bug was highlighted by L2 community Abirtrum tech lead Lee Bousfield in an Oct. 18 Twitter publish, warning that “BitBTC’s Optimism bridge is trivially weak.”
Bousfield mentioned he revealed the Tweet because the “group has ignored my messages, so I’m going to publish the important exploit right here.”
BitBTC’s Optimism bridge is trivially weak. Their group has ignored my messages, so I will publish the important exploit right here. https://t.co/onyN9SzBjt
— Lee Bousfield (@PlasmaPower0) October 18, 2022
In response to Bousfield, the BitBTC bridge had a bug that might permit an attacker to mint faux tokens on one facet of the bridge, and swap them for actual ones on the opposite.
“The Optimism L2 facet of the bridge allows you to withdraw any token, and it let’s that token choose the L1Token tackle handed to the L1 facet of the bridge. Nonetheless, the L1 bridge fully ignores what the L2 token was, and simply goes forward and mints the arbitrary L1 token!” he wrote, including that:
“Which means an attacker might deploy their very own token on Optimism, give themselves all the availability, and set that token’s L1 Token to the actual BitBTC L1 tackle.”
For the bug to be exploited efficiently, Bousfield outlined that it might take “7 days to undergo, throughout which the L1 bridge might be fastened through an improve.”
Shortly after noting such, somebody went on to check that concept, with an attacker trying to withdraw “200 billion faux BitBTC from Optimism.”
The attacker reportedly claimed that it was merea check.
Bousfield additionally famous in a subsequent replace round 10 hours later that the bug had since been patched after he managed to get in touch with the BitBTC group.
Cointelegraph has reached out to the BitAnt group for affirmation on these particulars and can replace the story in the event that they reply.
Associated: Ethereum Alarm Clock exploit results in $260K in stolen gasoline charges up to now
Optimism developer Kevin Fichter on Oct. 18 confirmed that the bug was on BitBTC’s facet of issues, because it had used its personal customized bridge versus Optimism’s customary bridge it affords to companions.
Fichter additionally famous that belongings “apart from BitBTC are usually not in danger,” including that there was quite a lot of “time and power positioned into the usual bridge” and inspired folks to make use of the usual bridge “until you already know what you’re doing.”
