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r/coldcard: questions about Mk4 RNG reverse-engineering and a linked research collection

reddit-mk4-reverse-engineering-question

https://www.reddit.com/r/coldcard/comments/1vkogy3/coldcard_mk4_rng_weakness_full_reverse/

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1

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  1. Earliest copy held Current
    seen · Captured here 1,738 chars
    Extracted text as captured 
    post: 1vkogy3
author: pingbtcio
created_utc: 1786376667
title: Coldcard Mk4 RNG Weakness: Full Reverse Engineering & Recovery Framework
body:
I've been studying the published research on the Mk4 RNG vulnerability from July 2026. 



I came across this research collection: [github.com/0xchainintelligence/coldcard-research](http://github.com/0xchainintelligence/coldcard-research)



I'm trying to understand the technical details better. Specifically:

\- How does the Yasmarang PRNG fallback actually work?

\- What determines which UID/RTC ranges are affected?

\- Has anyone successfully reproduced the findings for defensive testing?



Not looking to break any rules — just trying to understand the security implications for my own wallet setup.



DM if you've done similar research.

comment: p2xt7gt
parent: t3_1vkogy3
author: RevolutionaryPick241
created_utc: 1786405781
edited: false
body:
So, you created your account to post your own repo you recently created asking for dm? Does it work?

comment: p2yv9s4
parent: t3_1vkogy3
author: Korat_Bear069

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