Qubic Claims Successful 51% Monero Network Takeover - Unchained

Qubic, a project led by former IOTA co-founder Sergey Ivancheglo, claims to have achieved majority control of Monero’s hashrate, reaching 51% dominance after “a month-long, high-stakes technical confrontation.”

This level of control theoretically allows Qubic to reorganize blocks, censor transactions, and attempt double-spends on Monero’s privacy-focused token XMR.

The project deployed a “useful proof-of-work” model that converted XMR mining rewards into USDT, then used those proceeds to buy and burn QUBIC tokens, strengthening its own ecosystem while increasing its hashrate share on Monero.

Blockchain data shows that Monero experienced a 6-block deep chain reorg, a scenario where the blockchain replaces the last six blocks with a different set due to finding a longer competing chain.

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While some developers, like Serai DEX lead developer Luke Parker, contested that it constitutes a successful 51% attack, others like Blockchain CEO Nikita Zhavoronkov argued that a malicious 6-block reorg is already a success even if it’s short-lived.

Zhavoronkov warned, “I’ve warned the Monero community several times about the low security budget. Bitcoin is next!”

XMR dropped as much as 13% to an intraday low of $244.42 on Tuesday.