With its price down by 46% over the last three years, Ethereum (ETH -0.55%) now confronts yet another problem. While it certainly won't be alone, the possibility of devastation is ahead.

But where there's danger, there's often opportunity, and for Ethereum, this is likely one of those times. The new threat could enable Ethereum to reverse its fortunes.

This major security risk is only going to get larger over time

As the cornerstone of the decentralized finance (DeFi) sector within cryptocurrency, Ethereum needs to have its users' trust. A big part of that trust is built on the security features of the chain. There's not much point in investing in a chain or developing an application there if your money can easily be liberated from your wallet by a hacker.

It isn't always possible for a chain's developers to foresee threats. But right now, one potentially severe threat in particular is getting a lot of attention.

You've probably heard of quantum computers, which may in the future be able to perform certain tasks like cryptographic codebreaking far more efficiently than the classic computers that we use every day. Therefore, there is also a risk that a future quantum computer might be powerful enough and its users sufficiently adept to crack the encryption used for blockchains like Ethereum's. Such attackers could steal vast sums of cryptocurrency and potentially destroy a blockchain's entire ecosystem overnight. This is one of the few things that could make Ethereum go to zero.

There is no risk of that happening today. It's also unclear precisely when or if quantum computing will become advanced enough to pose an immediate threat. Nonetheless, the issue is already on the radar of most of the core development teams of the largest cryptocurrencies, and Ethereum is no exception.

The Ethereum Foundation, a nonprofit that is effectively the governance council of the chain, is investing in a research initiative with the mandate of making the chain secure via post-quantum cryptography (PQC), meaning cryptography resistant to threats from quantum computing. It is also in the process of considering whether to adopt a few other proposals for fortifying Ethereum against the quantum computing threat. While any implementation of those proposals is at least a few years away, the chain is far ahead of its competitors in its planning process.

Look for some implementation before getting bullish

Ethereum's early progress in preparing for quantum computing is important because it shows that security is a serious focus for the chain. But investors won't buy a coin based on the future security characteristics of its chain alone, and you shouldn't, either, at least not yet.

Make no mistake: Ethereum is currently the major chain that is among the least likely to fall victim to a quantum computing-based exploit, on the basis of its work in evaluating proposals and funding research into mitigation strategies. As (and if) the threat nears, that could make it more and more valuable. Eventually, it could make Ethereum a coin worth buying, especially if its competitors fail to keep up with its preparations for the future.

But the threat is still abstract. And investors shouldn't merely settle for discussion of risk mitigation measures; there's no real value in being added to the chain until it upgrades its tech. So keep an eye on Ethereum in the context of this issue.

If it stays ahead of the pack in preparing for quantum computing, that will be a bullish sign that Ethereum desperately needs right now.