Sui Blockchain Experiences Three Outages in Two Days Due to Upgrade Bug

The Sui blockchain has faced significant reliability issues in recent weeks, with three separate outages occurring in just two days. According to an official post-mortem analysis, all three incidents were linked to a bug caused by interactions between a new address-balance feature and the network's gas-charging logic.

The first outage began on May 28th and lasted for approximately seven hours, stemming from a rare issue in how the network charged gas for transactions paying with a mix of traditional coin objects and the new address-balance feature. Validators crashed due to an underflow error when trying to spend funds from canceled transactions.

An interim fix was implemented on May 28th to address the most common version of the bug, but it carried a known risk of causing another halt. Unfortunately, this risk materialized the next morning when a transaction triggered a masked variant of the same bug, bypassing the interim patch. A more robust fix was eventually developed and implemented by validators.