Core DAO launches emergency hard fork after validator reward anomaly

Core DAO disclosed that a limited number of validators were able to claim CORE rewards exceeding the blockchain’s designed issuance. The project has contained the issue and is coordinating an emergency hard fork that will modify network rules without reversing any confirmed transactions.

Emergency upgrade details

The planned fork is a forward upgrade, meaning previously recorded transactions will remain unchanged. Core said the upgrade will prevent further excess rewards and that assets remain safe. A full technical post‑mortem will be published after the response is completed.

Exchange response

Several centralized exchanges restricted CORE deposits and withdrawals following the announcement. Coinbase paused CORE sends and receives while keeping trading functions active. South Korean exchanges Bithumb and Coinone suspended CORE deposits and withdrawals, citing security concerns. Bitget and LBank also limited CORE transfers, describing the actions as wallet maintenance or project‑required suspensions.

Unresolved questions

• The amount of excess CORE issued has not been disclosed.
• The number of validators involved and the duration of the reward abuse remain unknown.
• It is unclear whether any of the additional tokens entered the market.
• Details of the technical vulnerability that allowed the over‑issuance have not been released.

Context and network background

Core operates as a Bitcoin‑linked sidechain using a delegated proof‑of‑stake validator set. As of early 2025, the network held over $525 million in total value locked and secured its chain with roughly 55 % of Bitcoin’s hash rate. The validator set previously numbered 23 during Q2 2024.

Comparison with recent hard forks

Other blockchains have recently executed hard forks to address protocol issues, such as BNB Chain’s Pasteur fork and Cardano’s van Rossem upgrade. Core’s emergency fork differs in that it is a reactive measure to a reward‑distribution anomaly rather than a scheduled protocol improvement.