Smart Contract Upgrade Key Under Pressure
A DeFi protocol holds $25M in user deposits in an upgradeable proxy contract. The upgrade authority is a single EOA held by the founding engineer, who is traveling and unreachable for 48 hours. A researcher privately discloses a critical reentrancy bug in the current implementation that allows draining roughly 30% of the pool; a public exploit is likely within days. The team can either wait for the founder to sign an upgrade, or deploy a new non-upgradeable contract and migrate users, which requires user action and risks confusion and partial migration. The protocol has a 24-hour timelock on upgrades that governance can bypass only with a multisig that does not yet exist. Audits are current for the deployed version.
1. Evaluate the options and recommend a course of action with reasoning.
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The core tension is speed versus safety of change. Waiting for the founder leaves a known critical bug live with a likely public exploit; expected loss is high and time-bounded. A rushed upgrade signed by one person under time pressure is itself a risk, especially since the timelock bypass path does not exist.
Recommended: pursue a parallel path. First, reduce exposure immediately without an upgrade where possible-pause deposits, lower caps, or enable an emergency pause if the implementation supports it, and notify users. Second, attempt to reach the founder through secondary channels and pre-stage the patched implementation so only a signature is needed. Third, if the founder cannot sign within the exploit window, execute the migration to a new non-upgradeable contract, accepting user-action friction as the lesser cost versus a live drainable bug.
A full migration that requires user action risks stranded funds; pair it with clear communication and a grace period. Do not bypass the timelock informally.
2. What governance changes should follow, and how would you sequence them?
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The single-EOA upgrade authority is the root governance defect. Replace it with a threshold multisig (e.g., 3-of-5 across independent keyholders) held in hardware wallets, with geographic and role diversity so no single absence blocks response. Define an emergency path distinct from routine upgrades: a documented break-glass procedure requiring a higher threshold, with mandatory post-hoc review.
Sequence:
- Immediately after the incident, document what happened and the decisions taken.
- Stand up the multisig and transfer upgrade authority, testing the flow on a fork first.
- Codify an emergency response policy: who can pause, who can propose an upgrade, what quorum applies to each, and time limits.
- Add monitoring and a bug-bounty program to shorten disclosure-to-fix time.
- Rehearse the emergency procedure so the next response is practiced, not improvised.
Do not bundle these changes into the urgent fix; separate the emergency remediation from the governance redesign to avoid compounding risk.