TLDR
- Sui experienced three separate mainnet outages across May 28 and May 29 after a gas-charging bug surfaced.
- The Sui Foundation said the issue originated from a new feature introduced in the v1.72 release.
- Validators crashed when certain transactions triggered an underflow error during gas payment processing.
- A second fix resolved the gas bug, but a separate randomness-related issue caused another network halt.
- The Sui Foundation said no user funds were lost and no finalized transactions were reversed during the outages.
Sui has suffered three mainnet halts after a v1.72 feature exposed a gas-charging flaw, the Sui Foundation said in a Sunday post-mortem.
According to the Sui Foundation, the failures began on May 28 after a rare transaction case hit the network’s gas limit. The first halt started near 7 a.m. PT and lasted almost seven hours.
Sui Gas Bug Triggers Fresh Mainnet Halt
The foundation said the issue involved transactions that used both the new address-balance feature and older coin objects. When one transaction lacked enough funds, validators crashed because the system still tried to spend the same gas.
Sui restored the mainnet around 1:30 p.m. PT with an interim fix. The foundation said the patch solved the most common case, although it carried a low-probability halt risk.
The same risk appeared on May 29. The foundation said a second transaction used another cancellation path, which bypassed the temporary patch. Validators adopted a stronger fix by about 9:40 a.m. PT.
A third halt followed when validators restarted. According to the foundation, validator participation in Sui’s randomness system dropped below the required level, so the system disabled itself as designed.
Randomness Bug Extends Disruption
The foundation said another dormant bug failed to save that disabled state to disk. After the next restart, validators did not recognize that randomness had been turned off.
The next epoch change then stalled for nearly six hours as randomness-linked transactions waited in a paused queue. Apps using chance-based functions, including games or random NFT mints, depend on that system.
The Sui Foundation said no user funds were at risk and no finalized transactions were reversed during the outages.
The latest outages add to Sui’s reliability record since its 2023 mainnet launch. The network previously faced a two-hour transaction scheduling bug in November 2024 and a six-hour consensus divergence in January 2026.
