The army is at the city gates: Qubic launches a 51% attack on Monero coin, community bail-in for 72 hours.

Written by: Oliver, Mars Finance

In the rapidly changing narrative of the crypto world, some names seem to have faded from the spotlight. Monero is one of them. As a "living fossil" project that emerged in 2014, it does not promise astonishing yields like DeFi protocols, nor does it easily ignite social media frenzy like NFTs or Meme coins. For many years, Monero has acted like a silent craftsman, consistently focused on its original mission - to create a truly untraceable and unlinkable digital cash system. Its development does not seek immediate success but rather emphasizes continuous refinement of privacy technology and ongoing strengthening of network resilience.

However, this persistence has also placed the entire privacy track on a razor's edge. With the tightening of global regulations, privacy coins have become the "number one enemy" of compliance. Major mainstream exchanges have successively delisted them to avoid potential legal risks. From the outside, the challenges facing the privacy track mainly come from external pressure from regulatory agencies. However, no one anticipated that a more disruptive crisis would erupt from within the crypto world, directly targeting the most representative banner holder in this track.

On August 12, 2025, the emerging Layer 1 project Qubic released a brief but information-rich statement on social media: "The Monero (XMR) experiment is proceeding smoothly as planned, and everything will be revealed in due time." This tweet was like a thunderclap, bringing to light the nearly fatal network hash rate crisis that Monero was suffering from, and unreservedly associating itself with this storm. Was this a reckless display of skill, a deliberate attack, or a "social experiment" aimed at exposing the industry's ailments? To unravel this mystery, we must turn our gaze to the orchestrators of the storm.

Behind this storm is a figure who has made a profound mark in the crypto industry—Sergey Ivancheglyo (known in the community as CfB). His name is always associated with disruptive innovation. From pioneering the introduction of pure PoS (Proof of Stake) consensus for the NXT project in its early days, to later being a core force behind IOTA and bringing the groundbreaking technology of Directed Acyclic Graph (DAG) into the public eye, Ivancheglyo's career is itself a history of challenging existing paradigms. His split from the IOTA Foundation and the subsequent public debates surrounding the matter further highlight his tendency to operate outside traditional organizational frameworks, pursuing his technological vision in a purer and less constrained manner. Qubic is a continuation of this style—an latest attempt aimed at fundamentally redefining the value of PoW (Proof of Work).

"Useful" computing power and "economic attacks"

The core concept of Qubic is "Useful Proof of Work" (uPoW). Traditional PoW, as used by Bitcoin, has miners maintaining network security by solving meaningless hash puzzles, which is considered a huge waste of energy. Qubic, on the other hand, attempts to make this computational power "useful" by directing it towards fields such as AI training and scientific computing. Their system allows miners to perform these AI tasks while directing part of their computational power to mine on other PoW networks through a mechanism called "outsourced computing," with Monero being their first target.

The brilliance of this mechanism lies in its creation of a powerful economic incentive. Qubic miners not only receive their native token QUBIC as a reward but also gain additional profits from mining Monero. More disruptively, the Qubic team sells the mined XMR on the open market, using the funds to repurchase and destroy QUBIC tokens, creating deflationary pressure and thereby raising the price of QUBIC. This creates a dangerous flywheel: higher QUBIC prices attract more miners, more miners mean greater hashing power, and greater hashing power leads to more XMR being mined, which can further push up the price of QUBIC when sold.

This is not a traditional hash power attack, but rather an "economic attack." Qubic is not attempting to directly steal funds through double spending attacks, but instead utilizes a superior economic model to attract the originally dispersed Monero hash power around itself like a giant magnet. As analyzed by Protos Media, this is a "boiling frog" type of threat, which erodes the foundation of Monero's decentralization.

The troops are at the gates: The Monero community's counterattack

When the hash rate of Qubic in the Monero network surged from 25% in mid-July and reached the critical point of 48-50% on August 12, the Monero community felt a tangible chill. SlowMist founder Yu Xian confirmed on social media: "Technically speaking, Qubic has successfully executed a 51% attack on Monero." Although Qubic did not initiate a double spend, the security balance of the network has been completely disrupted.

A 51% attack is the sword of Damocles hanging over PoW chains. Historically, Ethereum Classic (ETC) lost assets worth $1.1 million to double-spending in 2019, while Bitcoin Gold (BTG) suffered losses of up to $18 million in an attack in 2018. The Block cites estimates from analysts stating that a malicious actor only needs to spend "$7,000 to $10,000 per day" to rent enough computing power to control the Monero network. Qubic's "experiment" has undoubtedly brought this theoretical risk vividly before the world.

Faced with the looming threat, this community, which bears the totem of "privacy" and "anti-censorship," has erupted with astonishing cohesion. A grassroots "hash power defense battle" quickly commenced. Community members rushed to inform each other on social platforms like Reddit, calling for all loyal miners to withdraw their hash power from unknown mining pools and transfer it to reputable defensive pools such as p2pool (a decentralized mining pool) or supportxmr.com.

The core of this counterattack is to weaken the foundation of the Qubic economic model. Although Sergei Chernykh, the developer of the mainstream mining software XMRig, denied the accusations of launching a DDoS attack on Qubic, he clearly stated that the community is exploring "completely legitimate countermeasures." Behind this is a struggle for the soul of the network.

"Please Do Not Resist": Philosophy, Hubris, and the Future

In the "Cycle 172 Review" blog post officially released by Qubic, they recounted the entire process of this "experiment" from an almost god-like perspective, even documenting how they activated the "selfish mining" mode in response to the community's backlash. Moreover, a remark from its founder Ivancheglyo in the community further heightened the drama of the event: "Please, do not resist."

This statement is full of provocation, but it also reveals deeper philosophical reflections behind Qubic's actions. In the eyes of Ivancheglyo and his supporters, if a PoW network can be easily suppressed in computing power by a superior economic system, then the problem lies in the design of the network itself, which is unfit in the sense of "evolutionary theory." Qubic's "experiment" is a stress test to examine the "immunity" of the PoW network. They believe they are not destroyers, but rather "whistleblowers" revealing the truth, forcing the industry to confront the possible vulnerabilities of the PoW mechanism at the level of economic incentives.

This undoubtedly touches on the core issue of the crypto world: what is the essence of decentralization? Is it the absolute physical dispersion of computing power, or a more resilient consensus model that can withstand external economic erosion? Monero's RandomX algorithm aims to resist ASIC mining machines to achieve fairness in CPU mining, and its original intention was to maintain decentralization. However, the emergence of Qubic proves that even achieving ultimate decentralization at the hardware level, the centralization of computing power based on economic incentives remains an unavoidable threat.

The impact of this incident is profound. It serves as a wake-up call for all PoW projects, especially those with smaller market capitalizations and lower security barriers in terms of computing power. Simply relying on technically sophisticated designs may not be sufficient to cope with the "dimensionality reduction strikes" from more efficient external economies. Future competition among public chains may not only be a contest of technology and ecosystems, but also a game of economic models and incentive mechanisms.

In the end, under the tenacious resistance of the Monero community and tremendous public pressure, the hash power share of Qubic has receded. This war without gunpowder has temporarily come to a halt. However, the issues raised by Qubic remain unresolved. It acts like a mirror, reflecting both the glory and the concerns deep within the PoW world. This controversial "experiment" initiated by a genius developer may not be the last. When the next, more powerful "Qubic" appears, who can guarantee that they won't become the next "Monero"? This game of hash power, sovereignty, and survival has only just begun.