Ethereum’s Fusaka upgrade reduced gas fees roughly sixfold and coincided with a large rise in address-poisoning (dust) attacks: daily dust transactions jumped from ~30,000 before Fusaka to an average of 167,000 after, peaking near 510,000. Researchers report victims lost more than $63 million in the two months after Fusaka (vs. $4.9 million in a comparable prior period), including a single $50 million USDT theft on Dec. 19, 2025. Analysts note booming stablecoin volume (about $7.5 trillion in a quarter) and warn that much-lower fees made mass poisoning cheaply scalable and that security trade-offs should have been addressed before the upgrade.

Fusaka materially lowered fees (~6x), which is temporally correlated with a documented rise in dust transactions (from ~30k to avg 167k/day, peak ~510k) and reported losses exceeding $63M in two months, including a $50M USDT theft; researchers explicitly warn lower fees enabled cheaply scalable attacks. These are concrete facts from the summary.