Cold wallet is the digital currency for non-network storage wallet, there is a professional hardware wallet, you can also use non-networking equipment to make cold wallet.

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The "cold storage wallet" on Exodus phones supports major virtual currencies including Bitcoin and Ethereum. The status of cold storage hardware is quite high for blockchain phones, adding a double layer of protection to the wallet because it means Exodus will be able to store the user's virtual currency offline.

Electrum Litecoin Wallet review: Lightweight Litecoin customers.

So what exactly is tBTC's solution? It is based on the above, using a multi-wallet multi-signature solution that eliminates a single point of failure.

In December 2018, Slow Fog first discovered and alerted an attacker to a messaging flaw using the Electrum wallet client, forcing an "update prompt" to pop up when a user transfers money, inducing users to update and download malware to carry out currency theft attacks.

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Attackers reportedly implemented a compromised version of their Own Electrum server hosting to enable hacking. When users synchronize their vulnerable Electrum wallet with a malicious server, they are instructed to "update" their clients with a hacker version, which can eventually result in the immediate loss of funds contained in older versions.

The UB team has now developed Core, Core-QT, Electrum Wallet (where Electrum is a lightweight wallet that supports multiple signatures) and released a complete blockchain browser. More than 18 trading platforms around the world support UBTC trading.

Electrum Wallet users lost $4 million to BTC in a series of phishing attacks.