The landscape of cryptocurrency has recently been disrupted by bold statements from a project named Qubic, spearheaded by IOTA co-founder Sergey Ivancheglo. They claim to have achieved a significant milestone by allegedly gaining control over the majority of the Monero blockchain’s hashrate. According to Qubic, this takeover was realized on August 11, 2025, after several weeks of concentrated effort. This dramatic development has stirred concerns over the security of Monero’s network and brought attention to the potential vulnerabilities facing mid-sized Proof-of-Work blockchains from targeted takeovers driven by economic incentives.
Recent Developments in the Monero Controversy
The Qubic team asserts that their takeover utilized an innovative model termed “useful proof‑of‑work” (uPoW). Through this mechanism, miners direct their CPU resources to mine Monero, with Qubic subsequently converting the mined XMR into USDT to either buy and burn QUBIC tokens or reward their validators. This strategic financial approach managed to divert a significant amount of Monero’s mining power, escalating from below 2% in May to the claimed 51% dominance by August. Qubic promotes this initiative as a controlled experiment aimed at exploring how financial incentives can realign control over a blockchain network.
In a notable twist, discussions on the social media platform X have revealed that there was indeed a six-block reorganization observed on the Monero blockchain, indicating that Qubic possesses enough hashrate to impact operations significantly.
Should Qubic maintain and solidify control exceeding 50% of Monero’s blockchain hashrate, the potential risks are alarming. With majority control, Qubic could censor transactions, execute double-spends, and manipulate the blockchain structure at will, thereby compromising the entire integrity of the network.
Insights from Industry Experts
The Monero developer community responded to these claims with caution, reaffirming that simple chain reorganizations don’t automatically indicate a successful 51% attack. Luke Parker, the lead developer at SeraiDEX, pointed out that a six-block reorganization paired with block orphaning does not conclusively denote a hostile takeover; rather, it implies luck on the part of a high-hashrate mining group.
Charles Guillemet, the CTO of Ledger, expressed significant concern regarding the feasibility of sustaining such dominance, estimating the costs related to hardware and maintenance could hit $75 million per day, casting shadows over Monero’s future viability almost instantly.
Many within the Monero community remain skeptical about the authenticity of Qubic’s claims. As shared by blockchain expert Leonardo Faoro and echoed by Monero founder Riccardo Spagni, effective control doesn’t always necessitate a complete 51% hashrate—around 35% is often sufficient when paired with timely execution.
The market’s reaction echoed this trepidation; following Qubic’s assertions, Monero’s price plummeted to around $245. At last check, the cryptocurrency is trading at $247—reflecting declines of 5.3% over the past day and 15.2% over the week.
Conversely, Qubic’s native token has ascended, registering a notable increase of 20.5% in just 24 hours.
