Singapore’s UniPass Plays Role in ERC-4337 Vulnerability Fix
Smart contract wallet provider UniPass and crypto infrastructure firm Fireblocks have successfully addressed a significant vulnerability in the Ethereum ecosystem.

Account abstraction vulnerability
This vulnerability, identified as the ERC-4337 account abstraction vulnerability, posed a critical security risk to hundreds of mainnet wallets. The joint effort between Fireblocks and UniPass was detailed in a blog post published to the Fireblocks website on Thursday.
This vulnerability, if exploited, could have enabled a malicious actor to execute a complete takeover of the UniPass Wallet by manipulating Ethereum’s account abstraction process. The vulnerability represented a substantial threat to the security of smart contract wallets, as it could lead to unauthorized access and fund drainage.
Improving user experience
Account abstraction, as dealt with via ERC-4337, is a mechanism that introduces a novel way of processing transactions and interacting with smart contracts on the Ethereum blockchain. It allows for a more flexible and efficient handling of transactions, transcending the traditional distinction between externally owned accounts (EOAs) and contract accounts.
EOAs are controlled by private keys and can initiate transactions, while contract accounts are governed by the code of a smart contract. When an EOA initiates a transaction with a contract account, it triggers the execution of the contract’s code. Account abstraction introduces the notion of abstracted accounts, which are not tied to a specific private key and can initiate transactions and interact with smart contracts, similar to EOAs.
In the context of ERC-4337, an account executing an action relies on the EntryPoint contract to ensure that only signed transactions are executed. Typically, these accounts trust a single audited EntryPoint contract to validate user operations before executing commands. However, the vulnerability resided in the fact that a malicious or buggy EntryPoint contract could potentially skip the validation step and directly call the execution function, bypassing essential security measures.
This vulnerability, identified by the two firms, had allowed attackers to seize control of UniPass wallets by replacing the trusted EntryPoint of the wallet. Once this takeover was completed, the attacker could access the wallet and drain its funds.
It’s worth noting that the vulnerability posed a threat to several hundred users who had activated the ERC-4337 module in their wallets, making them susceptible to exploitation by any actor on the blockchain. Fortunately, the wallets affected by this vulnerability contained only small amounts of funds, and swift mitigation efforts were successful in preventing further harm.
Company merger
Earlier this year, Singapore’s UniPass merged with Chinese wallet provider Keystone to form Account Labs, a company which has been incorporated in Singapore. At the time, Keystone founder Liu Lixin outlined that further developing account abstraction-derived products was the objective of the creation of Account Labs. He stated:
“We are on the cusp of a Web3 Account Abstraction revolution. Together, we’ll drive rapid transformation, making the transition from Web2 to Web3 effortless for users. Our goal is to ensure everyone can securely and smoothly manage a decentralized account. We welcome partners to join us in advancing the Web3 account domain.”
In furthering that objective, Account Labs announced on Thursday that it had raised $7.7 million in a funding round led by Amber Group, MixMarvel DAO Ventures, and Qiming Ventures.


