Monero Surges 7% Despite Historic 18-Block Reorganization Raising Security Concerns

Monero Experiences Record 18-Block Reorganization Amidst Security Concerns

On Sunday, Monero (XMR), a leading privacy-focused cryptocurrency, underwent an unprecedented 18-block blockchain reorganization. This event reversed approximately 117 transactions and has alarmed the community about the network’s security and future stability.

The reorganization was orchestrated by Qubic, a layer-1 AI-centric blockchain and mining pool that recently acquired over 51% of Monero’s network hashrate. This follows a prior six-block reorg executed by Qubic last month, signaling a persistent threat to the network’s integrity.

The reorg commenced at block 3,499,659 at 5:12 am UTC and concluded at block 3,499,676 roughly 43 minutes later, as confirmed by Monero node operators who shared real-time command-line data on social media platform X. Cryptocurrency protocol researcher Rucknium also verified the event on GitHub.

Price Reaction Contrasts with Security Breach

Interestingly, Monero’s token price remained relatively stable during the reorganization process. However, just over eight hours later, XMR rallied 7.4%, climbing from $287.54 to $308.55 according to CoinGecko data. This gain occurred despite a roughly 1% decline across the broader cryptocurrency market on the same day.

Crypto podcaster xenu, an early reporter of the incident, speculated that Qubic’s actions might be aimed at stemming the decline of Monero’s price amid growing network instability.

Community Debates Network Reliability and Future Safeguards

This 18-block reorg, potentially the largest in Monero’s history, has intensified debate within the community regarding the chain’s resilience. The repeated attacks underscore how proof-of-work blockchains remain vulnerable when mining power is overly concentrated.

Some critics have expressed serious doubts about Monero’s reliability. Notably, crypto commentator Vini Barbosa announced on X that he would cease accepting XMR for payments until the network’s security issues are resolved.

Potential Measures to Mitigate 51% Attack Risks

Rucknium suggested that Monero node operators might begin adopting Domain Name System (DNS) checkpoints, where nodes reference trusted community DNS servers to verify block data, as a temporary defense against further reorgs. However, this approach could increase centralization, a concern already heightened by Qubic’s dominant hashrate.

Yu Xian, founder of blockchain security firm SlowMist, warned on X that without serious community action, the threat of reorganization will persist as a looming risk over Monero.

In the past, the Monero community has explored multiple strategies to reduce susceptibility to 51% attacks. Proposals have included localizing mining hardware, switching to alternative mining algorithms, enabling merged mining with Bitcoin, and adopting ChainLocks similar to Dash’s protocol. None of these solutions have been implemented to date.

Monero’s existing safeguard—a 10-block lock to protect transactions from reorgs—was insufficient in this case, as the recent reorganization spanned 18 blocks.

Market Impact and Outlook

Despite these security breaches, Monero’s token price has shown resilience, declining only 5.85% since Qubic’s initial takeover of hashrate in late July. The recent price rally suggests market participants may be weighing Monero’s privacy features and long-term potential against immediate security concerns.

As the community considers trade-offs between decentralization and security, the path forward for Monero remains uncertain. Monitoring developments around consensus upgrades and mining power distribution will be critical to assessing the network’s stability.