Qubic has announced that it now claims to possess majority control over the Monero hashrate, a development that has sparked concerns and fears regarding the potential for a 51% attack on the network. This situation raises significant alarms within the cryptocurrency community, as a 51% attack could allow Qubic to manipulate transactions, double-spend coins, and undermine the overall security and integrity of the Monero blockchain. As a result, many users and investors are apprehensive about the implications of such concentrated power in the hands of a single entity that could jeopardize trust in the decentralized system.
source: https://www.coindesk.com/business/2025/08/12/qubic-claims-majority-control-of-monero-hashrate-raising-51-attack-fears