Sui Mainnet Halts Tied to Upgrade Bug After Three Stops in 48 Hours
Sui’s mainnet went down three times in 48 hours after developers linked the repeated outages to bugs introduced by a protocol upgrade, raising fresh questions about the network’s reliability.
The Sui Foundation confirmed that the network experienced three separate outage incidents on May 28 and May 29, 2026. The first halt began around 7 a.m. PT on May 28 and lasted until roughly 1:30 p.m. PT. A second outage followed the next morning, running from about 5 a.m. PT to 8:30 a.m. PT on May 29. The third struck that same afternoon, from approximately 1:30 p.m. PT to 7:20 p.m. PT.
The clustering of three mainnet halts within such a short window is unusual even by the standards of younger Layer 1 networks, where occasional downtime is not unheard of. For Sui, a network holding roughly $745.6 million in total value locked, the disruptions put a spotlight on upgrade processes and validator coordination.
Crash Bugs in Gas Logic and a Latent Randomness Flaw
The Sui Foundation said the first two outages stemmed from crash bugs in gas charging logic that were introduced alongside the v1.72 release, which added a new address-balance feature. The bugs caused validators to crash, halting block production until patches could be deployed.
The third outage had a different root cause. A latent bug failed to preserve disabled randomness state across validator restarts, which meant the next epoch change stalled after validators were brought back online following the second fix. In effect, the remedy for the earlier crashes exposed a previously hidden flaw.
The foundation stated that no user funds were at risk during any of the three incidents and that the network did not revert any committed transactions. Sui’s status page marked the full incident resolved on May 30, 2026, noting the network had reached up to 93% participation by stake at that point.
SUI Token Slipped as Broader Sentiment Turned Fearful
SUI was trading at $0.8756, down 2.89% over 24 hours, around the time the outage sequence was being resolved. The token carries a market capitalization of roughly $3.5 billion with 24-hour trading volume near $470 million.
The broader crypto market was already under pressure, with the Fear & Greed Index sitting at 29, firmly in “Fear” territory. That backdrop made it difficult to isolate exactly how much of SUI’s decline was driven by the outages versus general market weakness.
What the Repeated Halts Mean for Sui’s Reliability
Three halts in 48 hours, two from the same upgrade and a third exposed by the recovery process, point to gaps in pre-release testing and validator restart procedures. The fact that a known upgrade introduced two distinct crash paths suggests the v1.72 release was not fully stress-tested against edge cases in gas charging logic.
The incident also highlights a broader challenge facing high-throughput Layer 1 networks: upgrades that add new features can interact unpredictably with existing subsystems. In this case, the address-balance feature shipped with v1.72 carried unintended side effects that only surfaced under mainnet conditions.
For users and developers building on Sui, including those already navigating rising security threats across crypto applications, two takeaways stand out. First, the foundation’s assurance that no funds were lost and no transactions were reverted is significant, as it means the network’s safety guarantees held even as liveness failed. Second, the speed at which a single upgrade produced three separate outages underscores the importance of staged rollouts and canary deployments for protocol changes.
The Sui Foundation has not yet detailed specific process changes it plans to adopt, but the sequence of events, documented publicly on its blog and status page, gives the community a concrete baseline against which to measure future upgrades. As institutional and retail participants increasingly evaluate Layer 1 networks alongside developments like new compliant trading products and large-scale enforcement actions, sustained uptime will remain a key differentiator.
Disclaimer: This article is for informational purposes only and does not constitute financial or investment advice. Cryptocurrency and digital asset markets carry significant risk. Always do your own research before making decisions.
