Overview
- Europol published two reports on October 7 calling on policymakers and the crypto industry to begin preparing now for quantum threats to keys and long‑lived encrypted data.
- The agency found the primary risk is exposed wallet public keys because a powerful quantum computer could derive the matching private key and authorize transfers without the owner’s consent.
- Blockchain analytics firms estimate about 6.0–6.9 million BTC sit at addresses with on‑chain public keys already exposed, and those funds cannot be made safe without owners moving them to new wallets.
- Europol warns migration will be slow and costly because post‑quantum signatures are much larger and a 2024 study cited by the agency estimates moving every Bitcoin UTXO could require at least 76 days of cumulative blockspace, creating congestion, higher fees and complex coordination across developers, custodians and users.
- The companion report flags 'harvest now, decrypt later'—collecting encrypted data today to break later—but finds no clear evidence of large‑scale exploitation now and recommends EU‑level coordination, wallet key‑management improvements, and phased testing of post‑quantum systems.