Backdoored Bitcoin/Monero hardware wallets are much more of a threat than Quantum computing.
There is zero credible evidence that Quantum can be engineered to scale cheaply and reliably enough to be broadly useful, and yet most of the attention is focused on Quantum and not the very likely case that most of the main hardware wallets are backdoored.
This video is great:
https://www.youtube.com/watch?v=lCKq9u-AL0AIf you spend some time doing objective research, you'll likely come to the conclusion that there is no neat solution that makes you "immune to the NSA". The best you can do is:
- Make mass, silent theft via one corporate/vended rail impossible,
- Force any serious adversary into messy, noisy, manual operations if they want you specifically.
The only real structural defense is collusion forcing:
- Heterogeneous multi-sig (different vendors + DIY),
- Multi-source entropy (XOR’d seeds),
- Passphrases kept off the compromised device,
- Independent stacks for different key shares.
A state-level actor can plausibly:
- backdoor RNG/nonces,
- exfil keys via signatures,
- coerce vendor into "minor tweaks",
- intercept shipping,
- or just use host+legal leverage.
There are very many attack vectors and in some places, you just have to trust as you can't verify.
Some of the attack vectors:
- Closed-source secure elements with opaque behavior.
- Compromised RNG -> predictable keys.
- Firmware "updates" that:
(a) leak shards,
(b) weaken PIN delays,
(c) selectively target flagged serials.
- Supply chain substitution:
(a) devices swapped in transit,
(b) chips with additional logic embedded.
If we assume Controller-grade adversaries and cooperation leverage over:
- silicon vendors,
- big wallet brands,
- customs/parcel systems,
then for mass-market users:
- "self-custody" often means: "I'm holding a compromised device that behaves like self-custody until it's politically useful to make it misbehave."
And of course, they don't need 100% coverage. If they can de-risk 80-90% of "self-custody" BTC/Monero via:
- hardware design,
- vendor pressure,
- update channels,
then most people hold just another pool of conditionally controllable assets.
Even if they never fully exploit it, the option exists.
If you think hardware wallets being compromised is a bit of a stretch, maybe look into Dual_EC_DRBG, operation Bullrun, Edgehill, the company Crypto AG, operation Rubicon, etc.
Who knows what sorts of stuff people like Adam Back and co are up to.
