thecybersecguru
@thecybersecguru@infosec.exchange
infosec.exchange
🚨 BREAKING SECURITY ALERT — COLDCARD FIRMWARE INCIDENT🚨
Coinkite has issued an urgent advisory affecting COLDCARD hardware wallets after discovering that certain firmware versions reduced entropy during seed generation, potentially weakening the randomness behind BIP-39 recovery phrases.
This comes in the wake of a coordinated theft of ~594.48 BTC (~$38M) from roughly 500 wallets in ~25 minutes. While the timing is alarming, Coinkite has NOT confirmed any direct link between the firmware issue and the theft. Investigation is ongoing.
⚠️ What’s critical right now:
• Affected firmware may have produced weaker-than-expected seed entropy
• Firmware updates do NOT fix seeds already generated on vulnerable versions
• Any wallet created under affected conditions may be at long-term cryptographic risk
🚨 Immediate guidance:
• Mk3 users: migrate funds immediately unless you verifiably used strong external dice entropy
• Mk4 / Mk5 / Q users: update firmware immediately before generating any new seeds
• Treat all affected seeds as potentially compromised until independently verified
This is a seed-generation integrity issue, not a typical wallet exploit — meaning the risk is silent, persistent, and irreversible once a weak seed is created.
I’ve broken down the technical root cause, entropy failure mode, and mitigation steps here:
https://thecybersecguru.com/news/coldcard-seed-generation-firmware-flaw-bitcoin-wallets/
#BREAKING #Bitcoin #HardwareWallet #Cybersecurity #BIP39 #Cryptography #Infosec