Sui Mainnet Restarts After Three Outages Tied to Bugs in v1.72 Release
Sui (SUI) says its mainnet has returned to normal after three separate halts over May 28–29, 2026, with all incidents traced to bugs introduced in the v1.72 software release. During each interruption, block production paused as validators coordinated fixes and restarted the network.
The first halt began around 7:00 a.m. PT on Thursday and lasted until about 1:30 p.m. PT. Sui’s v1.72 upgrade added a new mechanism allowing users to pay transaction fees from so-called address balances. A bug surfaced when two transactions attempted to spend from the same address balance simultaneously and one was canceled. Despite the cancellation, the network still tried to charge the fee, producing an invalid negative balance that ultimately crashed the system.
Validators initially deployed an interim fix to restore service, though the team noted it carried a known edge case. That scenario occurred around 5:00 a.m. PT Friday, when a different error code overwrote the original cancellation reason and bypassed the safeguard, triggering a second halt. A more complete fix was rolled out by 8:30 a.m. PT.
A third outage, running from roughly 1:30 p.m. to 7:20 p.m. PT on Friday, stemmed from a separate issue tied to an epoch transition. At the start of each new epoch, validators run a setup process that generates a shared random value used by certain transactions. After validators restarted to apply the morning fix, too few participated in the setup process, leading to the process being disabled for that epoch. A latent bug prevented that outcome from being written to disk. When validators restarted again, they did not retain the failed setup state and continued waiting for a result that would never arrive, stalling end-of-epoch logic and halting the network.
Sui’s Core Team said user funds were never at risk and the network did not roll back any previously confirmed transactions. The SUI token is trading around $0.88, down 2.57% over the past 24 hours, with a market capitalization of about $3.5 billion, ranking No. 32.
Following its incident review, the team outlined three investment priorities: improving end-of-epoch resilience, refactoring gas-charging logic to make it more modular and testable, and adding failure containment so a single bad input cannot halt the entire network. The update comes after Sui’s earlier $10 million security commitment following the Cetus hack, as the chain remains under scrutiny for operational stability and its ability to resolve network bugs quickly.
