Sui mainnet resumes after three 1.72 outages; no funds lost

Sui’s mainnet resumed normal operations after three network halts on May 28 and May 29, 2026. Validators traced the interruptions to bugs introduced in the 1.72 software release and coordinated fixes to bring the chain back online.

The first outage began about 7:00 a.m. PT on May 28 and lasted until roughly 1:30 p.m. PT. The 1.72 release added an option to pay transaction fees from address balances. When two transactions tried to spend the same address balance at once, one transaction was cancelled but the system still attempted to debit the fee, producing an impossible negative balance that crashed the network.

Validators applied an interim patch to restore service, but a known edge case surfaced on May 29 at about 5:00 a.m. PT. A different error code replaced the original cancellation reason and bypassed the guard in the interim fix, triggering a second halt. A more complete repair was deployed by about 8:30 a.m. PT that addressed the error-code handling.

A third outage on May 29, from roughly 1:30 p.m. to 7:20 p.m. PT, had a separate cause tied to epoch transition logic. When the network moves to a new epoch, validators run a setup that generates a shared random value used by some transactions. After the morning fixes, not enough validators completed that setup and the process was disabled for the epoch. A latent bug prevented the disabled state from being written to disk. When validators restarted, they expected a result that had never been produced, end-of-epoch logic stalled, and the network halted.

The Sui Core Team confirmed no user funds were at risk during the incidents and that the network did not revert any previously confirmed transactions. SUI traded around $0.88 after the outages, down about 2.6% over the prior 24 hours, with a market capitalization near $3.5 billion and a ranking around 32.

In a public message the team wrote: “Following last week’s outages related to the 1.72 release, the Sui Core Team has completed an investigation and incident review, detailing what happened and the steps taken by validators to restart the network.” The post-mortem said the team will strengthen end-of-epoch resilience, refactor gas-charging logic to make it more modular and testable, and add failure containment so a single bad input cannot stop the entire network.

The incidents follow Sui’s earlier $10 million security commitment made after the Cetus hack.