Monero developers debate consensus changes after Qubic 51% attack

Monero developers are discussing changes to the network’s consensus mechanism after the Qubic mining pool claimed majority hashrate control on August 12. The incident prompted Kraken to temporarily halt XMR deposits and implement stricter confirmation requirements.

Qubic announced it controlled over 50% of Monero’s mining power in mid-August, raising concerns about potential chain reorganizations and transaction censorship. Community members reported that a six-block reorganization occurred during this period, though some dispute whether Qubic achieved true majority control.

Kraken paused Monero deposits on August 15 and resumed them three days later with a 720-confirmation requirement. The exchange cited “consolidation of hashrate under a single entity” and warned it may halt deposits again, depending on network conditions. Kraken’s status page shows ongoing monitoring as of August 21.

Monero contributors are now evaluating several security proposals through the project’s Research Lab and community channels. Options include adding a ChainLocks-style finality layer similar to Dash’s system, where masternodes provide additional security above Proof-of-Work (PoW). Other proposals involve merging mining with larger networks, requiring miners to provide “local proof-of-work” using standard hardware, and implementing block-signing by miners.

Several proposed changes would require hard forks to implement. The community remains divided over both the severity of Qubic’s impact and which solutions to pursue.

Separately, Qubic conducted a community vote suggesting Dogecoin as a potential future target. However, the pool’s founder stated such mining would require months of development work and that Qubic remains focused on Monero operations.

Monero uses the RandomX algorithm designed to favor CPU mining over specialized ASIC hardware. Despite this design, hashrate concentration in single pools can still enable deep reorganizations when crossing the 50% threshold, which prompted the current security review among network contributors.