Reproducible firmware and chain investigation

alvap-weak-rng-research

https://raw.githubusercontent.com/alva-p/coldcard-weak-rng-research/main/README.md

Organisation

Álvaro P.

Evidence role

Independent primary analysis

Published

2026-07-31

Source changes

0

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Independent re-derivation of fix commits, on-chain movements and vulnerable versus patched firmware symbols. Its README excludes real-seed recovery and labels unfinished work explicitly; deeper repository files include public transaction identifiers and are not mirrored by this archive.

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1. Earliest copy held Current
   seen 1 Aug 2026, 05:59 UTC · Captured here text sha256 91a511b95f222418299efaae 3,273 chars
   Extracted text as captured

   # coldcard-weak-rng-research
   Independent, defensive investigation into the COLDCARD firmware entropy failure
   disclosed 2026-07-30/31 and the ~594.5 BTC coordinated sweep observed the same day.
   Everything here is verifiable: real commits, real blockchain data, real compiled
   binaries.
   **[📄 Read the report (English)](docs/en/report.md)** · **[📄 Leé el informe (Español)](docs/es/report.md)**
   ## What this is
   On July 30, 2026, roughly 594.5 BTC was drained from 500 Bitcoin addresses in about
   fifteen minutes. The victims used COLDCARD hardware wallets, and the root cause was a
   firmware bug that made supposedly random wallet secrets predictable. Coinkite (the
   manufacturer) and Block published official advisories. This repository does not just
   summarize those advisories, it independently re-derives the parts that can be
   re-derived: the fix commits, the on-chain flow of the stolen funds, and the bug itself,
   compiled and proven with real tooling.
   ## Three things you can check yourself
   1. **The code.** [`evidence/commits/findings.md`](evidence/commits/findings.md) verifies
      the fix commits directly against the Coldcard firmware repository, including one the
      official advisory doesn't mention.
   2. **The money.** [`evidence/onchain/`](evidence/onchain) traces the theft on-chain from
      scratch, starting only from the public consolidation address, not from any published
      transaction list. Result: 500 transactions, 1,324 UTXOs, ~594.5 BTC, matching public
      reporting. Every transaction ID is in
      [`drain-transactions.csv`](evidence/onchain/drain-transactions.csv).
   3. **The build.** [`evidence/builds/`](evidence/builds) compiles the vulnerable and
      patched firmware from source and uses `arm-none-eabi-nm` on the real binaries to show
      which function the "random number" call actually resolved to, before and after the
      fix. See [`comparison.md`](evidence/builds/comparison.md).
   ## What's not here
   No PoC that recovers a real seed, scans for vulnerable addresses, or moves funds that
   aren't the researcher's own, and none ever will be. See [`DISCLAIMER.md`](DISCLAIMER.md).
   A synthetic RNG simulator and a Bitcoin regtest demonstration are planned but not built
   yet; open items are tracked honestly in [`RESEARCH_GAPS.md`](RESEARCH_GAPS.md), including
   one significant one: the Mk3 fix version Coinkite announced (4.2.0) has no matching git
   tag as of this writing.
   ## Sources
   Every claim traces to a primary source (code, commit, or on-chain data) or a rated
   secondary source. Full list with reliability ratings in
   [`references/sources.yml`](references/sources.yml).
   ## How to cite this
   ```

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