Key Takeaways:
- Monero’s “Fluorine Fermi” update enhances defenses against spy nodes by refining peer selection to avoid suspicious IP subnets.
- The release (v0.18.4.3) improves network stability and strengthens privacy by guiding connections toward trusted nodes.
- This move adds to Monero’s broader strategy, including Dandelion++ and IP ban lists, to protect users from transaction tracing.
Monero has launched version 0.18.4.3 of its software, called the “Fluorine Fermi” update, to strengthen privacy and counter “spy nodes” that attempt to trace users’ transactions by linking them to IP addresses.
Announced via X, the release is labeled “highly recommended” and introduces a new peer selection algorithm that avoids connecting to large IP subnets often exploited by spy nodes.
We're excited to announce that CLI v0.18.4.3 'Fluorine Fermi' has been released!
— Monero (XMR) (@monero) October 9, 2025
'This is a highly recommended release that enhances protection against spy nodes.'
Instead, it directs users toward more trustworthy, privacy-friendly nodes.
Beyond improved privacy defenses, the update also includes stability and reliability enhancements.
Spy nodes have long been a concern for Monero’s community, which promotes measures such as running personal nodes and using routing tools that block malicious activity.
In late 2024, the Monero Research Lab proposed an IP ban list feature to target suspected spy nodes, though it acknowledged that attackers can easily change addresses.
Monero also employs the Dandelion++ protocol to obscure transaction origins and protect user anonymity.
Collectively, the Fluorine Fermi update represents Monero’s continued push to reinforce its decentralized network and uphold its core mission of ensuring anonymous, surveillance-resistant digital transactions.