Summary
Ketju does not approve the zkSync Era bridge: an emergency board can upgrade its contracts with no delay, and the operator can block user transactions, including withdrawals, through a filter that also acts with no delay. We found no defect in its proof system. Matter Labs’ ZK rollup uses SNARK validity proofs. Withdrawals become actionable three hours after execution, much faster than an optimistic rollup's seven days. L2Beat rates zkSync Era Stage 0. Its risk summary says a malicious upgrade could steal funds, because the EmergencyUpgradeBoard can skip the standard upgrade delay of 4 days 3 hours to 8 days 3 hours entirely. Ketju does not approve Robinhood Chain for a similar censorship filter. In April 2025 an attacker compromised a privileged key inside Matter Labs, which adds to the structural concern.
Review triggers
- The TransactionFilterer is removed, or is shown to require the same delay and approvals as a standard upgrade
- The EmergencyUpgradeBoard loses its power to skip the standard multi-day delay, or that power itself requires a minimum standing delay
- zkSync Era reaches at least Stage 1 under L2Beat's published criteria
- Twelve months in a row, counted from the April 2025 incident, with no compromise of a privileged key anywhere in Matter Labs or ZK Foundation governance or operations
Facts
- Verdict
- Not approved
- Type
- Other
- Chains examined
- Ethereum
- Reviewed
- Last confirmed