Ethereum's Fusaka upgrade on December 4, 2025, experienced Prysm node failures due to resource exhaustion from out-of-sync attestations, leading to missed epochs, an 18.5% missed slot rate, reduced network participation to 75%, and approximately 382 ETH in validator reward losses. Prysm nodes failed during heavy attestation loads in the Fusaka upgrade, causing about 18.5% missed [...]