Update (June 1, 2023, 7 AM UTC): This article has been updated to include the Tron team's responses.
A research team at dWallet Labs has discovered a zero-day vulnerability in Tron multisig accounts, allowing an attacker to bypass the multisignature mechanism and sign transactions with a single signature.
In a technical breakdown post, the research team said the vulnerability could have impacted $500 million in assets held in Tron multisig accounts. This is because it allows any signer to “completely overcome the multisig security offered by TRON.”
As its name suggests, multisignature wallets require multiple signers defined in an account to approve transactions and move funds, allowing the creation of joint accounts in crypto. Each account signer holds their own keys and the account requires a certain threshold for approving transactions.
According to the research team, the vulnerability with Tron’s multisig allows for generating many valid signatures. They wrote:
“We can bypass the multisig verification process by signing the same message with non-deterministic nonces of our choice. By doing so, we will be able to generate many valid different signatures for the same message by the same private key.”
According to the cybersecurity team, Tron ensures the signatures are unique instead of checking if the signers are unique. Because of this, signers can potentially “double vote” or sign twice. Omer Sadika, the CEO of dWallet Labs, said the fix was simple: verify the address instead of the number of signatures.
The researchers noted that the vulnerability was reported to Tron in February and fixed days after.
According to Tron, they were able to act swiftly upon receiving the report back in February. The Tron team told Cointelegraph that because it was fixed quickly, no one was able to exploit the vulnerability. They said:
"The fix is actually quite simple which involved modifying the verification process of multisig transactions to check the signed address against the list of addresses, strengthening the security of TRON's native multisig mechanism."
In other news, another decentralized finance protocol recently suffered a $7.5 million exploit. On May 28, blockchain security firm PeckShield reported that Arbitrum-based Jimbos Protocol was hacked, resulting in the loss of 4,000 Ether (ETH).