Product record · COLDCARD
COLDCARD Mk4
COLDCARD Mk4 Bitcoin-only hardware signing device in the COLDCARD lineage.
- Launch
- 2022
- Sales
- on_sale
- Support
- supported
- Variants
- —
- Confidence
- medium
- Last verified
- 2026-08-18
Material concerns
Custody and recovery assumptions
Active support, evidence verification, or product type is not a safety endorsement. Missing custody or recovery metadata is shown as unknown rather than inferred as self-custody.
- Custody model
- Unknown / not explicit in the canonical product record
- Key-management model
- Unknown / requires evidence review
- Independent recovery
- Unknown / requires evidence review
Lifecycle
Product timeline
COLDCARD Mk4 introduced
Product: COLDCARD Mk4
COLDCARD documentation records the Mk4 generation as introduced in 2022.
Seed-generation entropy defect disclosed
COLDCARD disclosed a seed-generation defect in affected firmware lines. Fixed releases restore the intended hardware-randomness path for future seed generation, but existing affected seeds require migration unless an advisory exception applies.
Fixed COLDCARD firmware released across supported model lines
Coinkite released fixed firmware for the supported COLDCARD model and track matrix and published migration guidance for existing affected seeds.
Sources