Qubic’s mining pool has gained significant influence over Monero’s network, causing unusual blockchain behavior such as reorganizations and orphaned blocks. While this activity is alarming, it doesn’t yet qualify as a full 51% attack.
Monero XMR $256.8 24h volatility: 1.2% Market cap: $4.75 B Vol. 24h: $65.80 M , the privacy-centric cryptocurrency, is currently facing troubling mining activity linked to the Qubic mining pool.
Recent observations show multiple orphaned blocks and significant reshuffling of the blockchain, raising fears of a potential 51% attack.
However, the current events do not yet amount to a full 51% attack. Instead, what we are seeing may be a combination of silent mining, block reorganizations, and empty blocks. These are all tactics that can be executed without controlling the majority of the network’s hashrate.
Some, however, have claimed that Qubic has already executed a successful 51% attack. If true, this would mean Qubic controls over half of the network’s total computing power, giving it dominance over other miners.
关注一段时间了，这次针对门罗币的 51% 攻击看来是成功了（感谢黑手册群友信息），不过成本也很高，最终不确定这样做的经济收益是什么…
现在理论上 Qubic 这个矿池可以重写区块链，实现双重支付，并审查任何交易…
相关平台注意可能的威胁，保持关注。 https://t.co/cKlMyuvy9C pic.twitter.com/U9J9bDiF85
— Cos(余弦)😶🌫️ (@evilcos) August 12, 2025
When a group gains this level of control, it can cause serious damage. It can rewrite parts of the blockchain’s history and can also block specific transactions, stopping them from being confirmed.
In effect, Qubic would have the power to decide which transactions are included in the blockchain and which are excluded.
Attacks like these are rare but can be very dangerous because they threaten trust in a cryptocurrency. If users start to believe that transaction records can be altered or their transactions blocked, they may lose confidence and stop using the network.
However, as mentioned above, the current events do not yet amount to a full 51% attack. A miner with a significant but less than majority share of the network’s power can sometimes produce multiple blocks in a row.
This may cause temporary blockchain reorganizations and orphaned blocks but cannot be maintained as a long-term attack without majority control.
A 6 re-org does not mean a '51% attack' was successful. In that case, we'd see unbounded-depth re-orgs/no blocks mined by any other mining pool (assuming the adversary censors other mining pools, as this one does).
It does mean an adversary with a high amount of hash got lucky.
— Luke Parker (@kayabaNerve) August 12, 2025
Ledger CTO Charles Guillemet warns that if the assault continues, confidence in the network could collapse in days. For now, the market reaction has been muted, as Monero has slipped by just 13%.
Monero appears to be in the midst of a successful 51% attack.
The privacy-focused blockchain, launched in 2014 and long targeted by governments and 3-letters agencies, is already banned from most major centralized exchanges.
The Qubic mining pool has been amassing hashrate for…
— Charles Guillemet (@P3b7_) August 12, 2025
Luke Parker, a top Monero developer behind the FCMP++ privacy upgrade, has proposed hard and soft fork solutions to improve resistance to attacks. He’s inviting new ideas from the community.
I made a meta-issue to discuss ways to change Monero to improve its resistance to bad actors. Included are both hard forks *and* less-invasive soft forks which would ideally improve Monero.
If you have legitimate, novel ideas, I'll be happy to incorporate them.
Link vvv
— Luke Parker (@kayabaNerve) August 8, 2025
Note that this story is still developing and there is quite a bit of misinformation surrounding it. We will continue to cover updates as more information becomes available.
Monero’s Recent Plights
Monero, a privacy-focused cryptocurrency launched in 2014 and already banned on many big exchanges, now faces one of its toughest moments.
Between August 6 and 7, five blocks were mined on the Monero chain but never added to the main blockchain. Orphan blocks like these happen when two miners produce blocks almost simultaneously, but only one gets accepted, and the others are discarded.
This unusual cluster of orphan blocks within just 720 recent blocks drew attention because such a frequency is uncommon in a short period. The situation grew more notable when CFB, a core developer from the Qubic mining project, posted a message online. Although not a direct admission, the tone and wording suggested Qubic could be involved.
Earlier this year, XMR’s price jumped 50% following a large-scale swap linked to the laundering of $330 million worth of stolen Bitcoin BTC $121 828 24h volatility: 2.3% Market cap: $2.43 T Vol. 24h: $50.85 B , highlighting the currency’s ongoing role in privacy-centric transactions.
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