- Organisation
- Bitcoin Optech
- Evidence role
- Secondary analysis
- Published
- 2026-07-31
- Source changes
- 0
- Detected differences
- 0
- Unreviewed
- 0
- Copies held
- 1
Newsletter #416 led with the incident. It carries the unitemised estimate 'exceed 1,000 BTC' and dates the theft transactions to 29 July, possibly consistent with a US-local date; the newsletter does not state a timezone.
Every check is recorded, including checks that found no text change. A detected edit is therefore bounded between two checks. The publisher's exact save time is not observable from this record. Last checked 2 Aug 2026, 01:00 UTC.
Snapshot and diff bodies for this chain monitor are held in the local evidence archive but withheld from the public site because they can contain victim addresses. Integrity hashes, capture times and reviewed change summaries remain available below.
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Recovered from the Internet Archive rather than captured by this project. The row records that third-party provenance separately from captures made by this project.
What changed from the previous capture 0 lines
Extracted text as captured
About Publications Topics Workshops Matrix en | ja | es | cs | hi | zh | de | fr | pt / home / newsletters / Bitcoin Optech Newsletter #416 Jul 31, 2026 This week’s newsletter warns about a severe vulnerability affecting wallets generated by COLDCARD signing devices, summarizes the disclosure of two denial-of-service vulnerabilities in Core Lightning, and describes a proof of concept for a zero-knowledge proof of reserves. Also included are our regular sections with selected questions and answers from the Bitcoin Stack Exchange, announcements of new releases and release candidates, and descriptions of notable changes to popular Bitcoin infrastructure software. Action items ● Move funds secured by COLDCARD-generated keys: if you used a COLDCARD Mk3 to generate a wallet, any funds received by that wallet are at risk of theft and should be carefully moved to an unaffected wallet as soon as possible. Wallets generated by other COLDCARD models may also be affected. See the News section below for details. News ● Wallets generated by COLDCARD at risk of theft: On 30 July 2026, some Bitcoin users discovered that funds from their COLDCARD wallets had been stolen in a series of unexpected transactions on 29 July. Over the course of the day, a bug was identified in the firmware of the COLDCARD Mk3 that causes wallets to be generated with insufficient entropy. As of this writing, estimated losses exceed 1,000 BTC, a figure that may continue to rise as the situation develops. A security advisory by Coinkite identified wallets generated by COLDCARD Mk3 using firmware version 4.0.1 (March 2021) or later,Excerpt only. The complete copy is held offline and backs quotations on this site. The original publication remains the canonical public source.
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