The Sui Foundation released a post-incident review on Sunday, confirming that the three mainnet outages on May 28th and 29th were all related to the address balance feature added in version 1.72. The problem arose because the new feature interacted with existing gas billing and consensus processes, triggering failures at different levels.

The first shutdown lasted nearly seven hours.

The first outage occurred around 7:00 AM Pacific Time on May 28th and lasted for nearly 7 hours. The foundation stated that a few transactions simultaneously used both the new address balance feature and the traditional coin object structure to pay fees. When a transaction was canceled due to insufficient balance, the gas processing flow still attempted to deduct the same amount of funds, ultimately causing the validator to experience an underflow error and crash.

The core team subsequently restored the network at approximately 1:30 p.m. that day and deployed a temporary fix. The foundation stated that the patch covered the most common triggering paths, but at the time it was known that there was still a low probability of causing another outage.

The second failure came from a variant of the same type.

This risk materialized the following day. The second shutdown occurred around 5 a.m. on May 29. A transaction triggered another variant of the same flaw: an insufficient balance error was overridden by a different cancellation reason, causing the temporary patch to fail to catch the issue.

The core development team then completed a more complete fix, and validators adopted it around 9:40 a.m. that day.

• The first shutdown lasted approximately 7 hours.
• The second shutdown occurred the following morning.
• A more complete repair was deployed at approximately 9:40 AM.

The third shutdown occurred after the restart.

The third failure was not a new, independent vulnerability, but rather a chain reaction following the second fix. When the validator restarted after installing the patch, the number of nodes participating in the on-chain random number protocol fell below a threshold, causing the system to automatically disable the random number function as designed.

However, the foundation stated that a latent flaw existed in the network that failed to write this "off" state to disk. As a result, validators were unable to recognize that the random number function was disabled upon the next restart, leading to a standstill during the next epoch switch. Transactions relying on random numbers continued to accumulate in the pause queue, and the outage was not resolved for nearly six hours.

Funds remained unaffected; SUI fell approximately 19% this week.

The foundation stated that user funds were not at risk during the three outages, and confirmed transactions were not rolled back. However, the market still reacted to the network's instability. According to CoinDesk data, SUI fell by about 8% during this series of outages, hitting a low of $0.90, with a cumulative weekly drop of about 19%.

This is Sui's third major stability event since its mainnet launch in 2023. Previously, the network experienced a two-hour outage in November 2024 due to a transaction scheduling flaw, and a consensus divergence lasting approximately six hours in January 2026.