Wallets · Hardware
COLDCARD
5 min read
What it is
COLDCARD is Coinkite's Bitcoin-only hardware wallet, designed for air-gapped signing (coldcard.com).
At a glance
| Spec | COLDCARD |
|---|---|
| Type | Hardware |
| Bitcoin-only | Yes |
| Open source | Not verified |
| Air-gapped | Yes |
| Multisig | Yes |
| Secure element | Yes (dual) |
| Price | Not verified |
Current security status
Advanced only: Advanced users only, new seeds only. Minimum version: Current 5.6.3 / 1.5.3Q (fix first shipped in 5.6.0 / 1.5.0Q). Checked 2026-10-16 on our security watch.
- A firmware RNG integration error produced weak seeds; affected seeds were brute-forced offline and thefts began July 30, 2026. The devices were not remotely hacked.
- Galaxy Research (Aug 14, 2026): 1,778.84 BTC high-confidence losses from 8,600+ addresses. Galaxy's Aug 25, 2026 update: about 1,789 BTC from 8,865 addresses, roughly 87% unmoved.
- Updating firmware does not repair an existing seed. Make a new seed on fixed firmware and move funds.
- Oct 11, 2026: an unauthorized phishing post appeared on COLDCARD's official X account and was deleted. COLDCARD warned on X not to visit or interact with the link, said its only official website is coldcard.com, and asked X to investigate. Never "migrate" funds through a link in a post.
- Mk2/Mk3: final firmware 4.2.0; not recommended for new use.
- Source: Coinkite advisory
- Source: COLDCARD security status
- Source: COLDCARD migration
- Source: COLDCARD downloads
- Source: Galaxy Research (Aug 14, 2026)
- Source: Cointelegraph (Aug 25, 2026)
- Source: BlockSec analysis
- Source: Cointelegraph: X phishing post (Oct 11, 2026)
- Source: COLDCARD on X (@COLDCARDwallet)
Key features
- Bitcoin-only (coldcard.com).
- Air-gapped signing with microSD; NFC and QR on some models (coldcard.com).
- Dual secure elements (coldcard.com FAQ).
- Multisig with desktop coordinators (coldcard.com tutorials).
Read the current status below before using a COLDCARD. Seeds made on affected firmware must be replaced, and updating firmware does not fix them.
Buying and setup
- Buy only from the maker's official site (coldcard.com) or an authorized seller it lists. Never use a device that arrives with a seed already written down.
- Set it up with our hardware wallet module, then pair it with Sparrow as a watch-only wallet.
Sources
Educational content only, not financial advice. See our disclosure.