Sui network stalls again after Thursday outage, resumes after

The Sui blockchain suffered a multi‑hour outage on May 28‑29, 2026, when a flaw in the gas‑charging logic of the 1.72 software release halted block production for almost six hours before validators applied a patched version and restored normal checkpoint flow [1].

Key takeaways

• The outage began after the 1.72 upgrade introduced a bug in fee calculation, freezing the network for 5 hours 55 minutes [1].
• Validators needed to upgrade more than two‑thirds of staked tokens to the patched code before the chain could resume, a process that took several hours [1].
• This is the second major stall in five months, the first occurring on Jan. 14 due to a consensus commit bug [1].
• No user funds were lost, and the network’s safety guarantees prevented data inconsistencies during the halt [1].
• SUI price fell 6‑8% to around $0.89 during the outage, then partially recovered after operations resumed [1].

Bug in the 1.72 release triggers network freeze

The 1.72 release added a new method for paying transaction fees using address balances. When two transactions attempted to spend from the same balance simultaneously, one was cancelled but the network still attempted to debit the fee, creating a negative balance and crashing the system [3]. Validators deployed an interim fix on Thursday morning, but a related edge case resurfaced on Friday around 5 am PT, prompting a second halt. A more comprehensive patch was applied by 8:30 am PT, restoring block production [3].

A third interruption occurred later that day during an epoch change. Validators run a setup process that generates a shared random value; insufficient participation disabled this process for the epoch, causing another brief stall that lasted until about 7:20 pm PT [3]. Each of these incidents stemmed from the same upgrade, highlighting the cascading impact of a single software bug on consensus and transaction processing.

Network recovery and market reaction

Recovery required coordinated action: validators holding more than two‑thirds of the staked tokens had to adopt the patched software before the chain could resume checkpoint production [1]. Once the upgrade was applied, normal block production restarted and transaction activity returned to pre‑outage levels [2]. The network’s design prevented any loss of user funds or data inconsistency despite the prolonged halt [1].

The outage immediately impacted the SUI token, with price dropping to roughly $0.89—a 6‑8% decline—before partially rebounding after the network resumed [1]. Analysts noted that the price movement reflected investor sentiment tied to the reliability concerns, especially given the recent history of a similar six‑hour stall in January [1].

Why it matters

The repeated multi‑hour stalls underscore the fragility of high‑throughput layer‑1 blockchains when critical bugs slip into upgrades. While Sui’s safety mechanisms protected user funds, the outages disrupted DeFi applications, halted trades, and introduced operational risk for exchanges and liquidity providers. The incidents have intensified scrutiny of Sui’s development and testing processes, and a detailed post‑mortem is expected to address how the bug evaded prior testing and what safeguards will be added to prevent future stalls. Continued confidence in the network will likely hinge on the effectiveness of those remedial measures and the ability of validators to coordinate swift responses to edge‑case failures.