3 August 2026
The Coldcard entropy failure exposed a trusted hardware-wallet bug. It also showed that open-source code, traditional audits, and even a single AI review are no longer enough. The next defensive step is a continuous, adversarial system of Swarm Audits.
The Coldcard situation is bad enough without trying to make it more complicated than it is. People generated Bitcoin wallets on devices they believed were secure, air-gapped and producing seeds from an almost unimaginably large field of possibilities. But after the firmware 4.x change, the seed-generation process was allowed to fall back to something far more predictable and that is BAD. Instead of an attacker having to search through a space approaching 256 bits of entropy (more numbers than stars in the known universe), some affected wallets were generated from a space small enough to attack with a laptop. The device never needed to touch the internet. The seed did not need to leak. An attacker could generate possible seeds somewhere else, derive the addresses and compare them against the public blockchain. That is how Bitcoin moved out of wallets that had been sitting offline, untouched and supposedly safe.
It should bother everybody that a Coldcard had the hardware and secure components to do the job right. It was a firmware change that sunk the boat. Coldcard also had the reputation. It had years of people, including me, telling other people that it was one of the safest ways to hold Bitcoin. I used one myself. I recommended it because I used it, and I was wrong. Somewhere along the way, we stopped treating “don’t trust, verify” as an instruction and started treating it as branding. We assumed the manufacturer had checked. We assumed somebody in the open-source community had checked. We assumed the experts had checked. Five years went by, and apparently NO ONE CHECKED.
Now we find ourselves on the other side of the Rubicon. We are not going back to the world where a company can say its product is secure, point to a repository, mention an audit from three years ago and expect everybody to relax with a beachfront Mai Tai. We are not going back to assuming that because code can be viewed, somebody competent has looked at every important part of it. And we are definitely not going back to believing that a hardware wallet is safe because enough podcasters, developers and influencers have repeated the same recommendation long enough. That world is gone. It may have never really existed, but the Coldcard failure burned away whatever illusion was left.
The problem is that the other side of the Rubicon is not comfortable. Large companies may be able to pay professional firms to perform deep audits every time something important changes. Hell, they may be able to do it every day at 8:00 pm. Smaller companies and open-source projects do not and will not have that kind of money. They may be building useful tools with three developers, a small budget and a community that desperately wants the project to succeed. A tiny mistake inside a tiny project can still destroy somebody’s future. So what are those projects supposed to do? They may have to accept community review on a scale that is confusing, noisy, repetitive and occasionally hostile. They may have to accept what I have started calling Swarm Audits.
A Swarm Audit is not a certification, one approved auditor or one artificial-intelligence model declaring that the code is clean. It is a lot of people using whatever they have. One person may understand the code deeply. Another person may know almost nothing about coding but has access to Grok, ChatGPT, Kimi or some other model and is willing to spend part of a monthly token allowance asking it to inspect a public repository. Somebody else may write a better prompt and post it on Nostr or X so other people can run the same review. Another person may take the results and explain why half of them are nonsense. Then somebody else runs it again with another model and finds something the first three missed. Now scale that to hundreds of people . . . thousands. It is not neat. It is not controlled. That may be the point.
I tried this myself with the BitBox codebase. I did not pretend I knew what I was doing, because at the level of coding and auditing code, I do not. It is better to admit that than fake it. I asked Grok to find the company’s repository, examine the code and report any vulnerabilities. I did not give it the repository address. I wanted to see whether it could find the code, determine what it was looking at and produce anything useful. It found the repository. It showed me the libraries, firmware and other parts of the codebase it was examining. Then it produced a report saying it found no major problem. Do I believe that means the product is safe? No. I believe almost nothing right now. That report was not a recommendation. It was one person, using one model, spending a small number of tokens to contribute one small piece of work.
Now imagine that happening thousands of times across open-source Bitcoin projects. Different people. Different models. Different prompts. Different levels of technical ability. Yes, there will be noise, false positives, hallucinated problems and people who do not understand what they are reading. There may also be malicious people trying to manufacture a convincing argument for removing a line of code that should remain exactly where it is. Nothing is off the table anymore. But I want to believe there are more good people than bad people. I want to believe that when enough independent people keep checking the work, the useful signal can eventually squelch the garbage.
The important thing is that this cannot become a flurry of activity that lasts two weeks and disappears as soon as everybody finds something else to argue about. Swarm Audits have to continue. Code changes. Firmware changes. Models improve. New vulnerabilities appear. A clean report today does not mean a project is clean six months from now, and one person saying “looks good” does not mean anything by itself.
We are on this side of the Rubicon now. That means smaller projects may have to open themselves to constant community examination, and the rest of us may have to contribute whatever skills, time, attention or tokens we can afford. We spent years saying not to trust but to verify. Now we may actually have to do it.
Coldcard entropy exploit
Coldcard hardware wallet vulnerability
Swarm Audits
AI security audits for Bitcoin
Open-source hardware wallet security
Member discussion: