Cryptocurrency wallets are the main point of exposure to future quantum attacks, Europol warns

A sufficiently powerful quantum computer could, in the future, derive a wallet’s private key from an exposed public key and enable transfers without the owner’s authorization, Europol warns. The agency says, however, that the risk does not mean the inevitable collapse of cryptocurrencies: the hash functions that protect blockchain integrity are comparatively more resilient, while the main challenge is migrating wallets and protocols to quantum-resistant cryptography.

Cryptocurrency wallets represent the main point of exposure for digital assets to future quantum attacks, according to a report published on Wednesday, October 7, by Europol’s European Cybercrime Centre. A sufficiently powerful quantum computer could derive a private key from an exposed public key and allow an attacker to authorize transfers without the owner’s consent.

In brief
Europol identifies wallet cryptographic keys as the main vulnerability of cryptocurrencies in the face of future quantum computers.

A sufficiently powerful system could deduce the private key from an exposed public key and enable unauthorized transfers.

Hash functions used to preserve blockchain integrity are comparatively more resistant to quantum attacks, so the risk should not be confused with an inevitable collapse of the entire technology.

Europol recommends a phased transition to quantum-resistant cryptography, improved wallet security and more robust key management.

The point at which quantum computers could become powerful enough for such attacks remains uncertain, and Europol does not claim that such thefts are already taking place.

Cryptocurrency wallets rely on pairs of cryptographic keys. The private key allows the owner to authorize transactions, while the public key enables the network to verify the signature. The issue described by Europol arises in a scenario where a sufficiently capable quantum computer could use an exposed public key to reconstruct the associated private key.

An attacker who obtained the private key in this way could sign transactions on behalf of the owner and transfer the assets controlled by the wallet. The report, however, examines a future technological capability. Europol emphasizes that it is not known when quantum computers might reach the level required to compromise the cryptographic systems used today.

This vulnerability differs from the hash functions that contribute to blockchain integrity, including by linking blocks and, on some networks, through the processes used for validation or mining. Europol considers these functions comparatively more resistant to quantum attacks than the public-key cryptography systems used to control wallets.

The distinction also changes how the risk should be understood. The report challenges the scenario in which the emergence of quantum computers would inevitably lead to the collapse of cryptocurrencies. The immediate challenge for the industry’s preparedness is protecting ownership of assets by updating keys, wallets and protocols before the technology needed for an attack becomes available.

Preparation is complicated by the decentralized nature of many networks. A cryptographic change does not depend on updating a single centrally controlled system, but may require coordination among developers, wallet operators, infrastructure providers, platforms and users. At the same time, new solutions must preserve network functionality and sufficient compatibility so that users can move their assets safely.

For this reason, Europol recommends a phased transition. Priorities include adopting cryptography resistant to attacks by quantum computers, improving wallet security and key management, and preparing protocol changes in advance. The agency also calls for clear information for users when migrating assets or updating wallets becomes necessary.

This approach is part of a broader European transition to post-quantum cryptography. In 2025, EU member states, with the support of the Commission, adopted a coordinated roadmap providing for the start of the transition to post-quantum cryptography by the end of 2026 and prioritizing high-risk systems. For critical cases, the European objective is to complete the transition as quickly as possible and no later than the end of 2030. These deadlines concern the broader European strategy for cryptography and do not represent a single legal deadline imposed on all cryptocurrency networks.

The Europol report does not announce a cryptocurrency theft carried out through quantum computing and does not set a date when such an attack will become possible. The agency’s argument is that uncertainty does not justify delaying preparations, because modifying cryptographic systems and coordinating a large-scale migration may take years.

The October 7 publication thus distinguishes between two risks that are often addressed together. In the case of cryptocurrencies, the main point of exposure is control of wallets through cryptographic keys. For other types of sensitive information, the concern is that encrypted data captured today could be stored and decrypted in the future. Europol examined this second scenario in a separate report published on the same day.

https://2eu.brussels/ro/news/portofelele-de-criptomonede-sunt-principalul-punct-de-expunere-la-viitoarele-atacuri-cuantice-avertizeaza-europol