History & Governance • Estimated 35m

COLDCARD RNG Incident

history.coldcard-rng-incident

A firmware integration mistake caused some COLDCARD models to generate wallet seeds through a predictable software PRNG instead of the intended hardware RNG. The incident shows how a plausible-looking random output, open source, and a released firmware binary can still leave users with a dangerously small key search space.

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Curated resources (3)

• COLDCARD Security Advisory (article) Official affected-model guidance, firmware versions, dice-entropy exception, and migration procedure.
• Technical Deep Dive into the Entropy Issue (article) Official technical explanation of the libNgU integration, fallback PRNG, model differences, and emergency fix.
• Predictable RNG Fallback and 32-Bit Reseed in COLDCARD Firmware (article) Independent technical analysis of the fallback path and limited reseeding behavior.

Direct prerequisites (2)

• BIP39 Mnemonics
• Random Number Generators

Direct dependents (0)

• None

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