The Sui Mainnet experienced three outages on May 28-29, 2026, due to bugs introduced during a recent protocol upgrade. The Sui Foundation reported that the interruptions were caused by flaws in the gas charging logic from the v1.72 release and a latent issue with validator randomness state preservation. Despite the disruptions, no user funds were at risk, and no committed transactions were reverted. The first two outages were linked to crash bugs in the gas charging logic, which led to network stalls when specific transaction patterns triggered an underflow. An interim fix was deployed, but it carried a low-probability halt risk that materialized, causing a second outage. The third interruption was due to a separate bug affecting randomness state during epoch changes. Mysten Labs addressed these issues with emergency fixes, restoring network functionality without affecting user balances. Sui's market capitalization stands at approximately $3.59 billion, highlighting the importance of network reliability. The outages have raised concerns about Sui's upgrade testing processes, especially following a similar incident in January 2026. The foundation's transparency in publishing a detailed postmortem is seen as a positive step, but the frequency of disruptions suggests a need for improved safeguards in future upgrades.