Blockchain.info Paper Backup Stores Private Keys in the Browser History

The first step in using any Bitcoin wallet should be to create a backup and store it securely. A Blockchain.info Web wallet supports backups through its Paper Backup feature. Use of this feature was found to store an unencrypted copy of the wallet’s private keys in the browser history. This unencrypted backup survived browser and system restarts. The first disclosures of this behavior appear to have been made more than six months ago on Bitcointalk and the Bitcoin subreddit.

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Who Needs Bitcoin Change Addresses Anyway?

Coin Jar

Few topics in Bitcoin cause more confusion, anxiety, and loss of money than change addresses. They seem counterintuitive and unnecessary. They're a major contributor to wallet software complexity. When used improperly, they can de-anonymize not just the payer but other parties as well.

Given the many problems with change addresses, why do they exist in the first place? This article explains what change addresses are, why they're essential to Bitcoin, and how to protect your money and privacy.

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Six Things Bitcoin Users Should Know about Private Keys

Keys

Private keys have been an integral component of Bitcoin since its first description in 2008. Wallet software generally protects users from the need to understand what private keys are and how they work. Even so, most users eventually come face to face with private keys, too often with unpleasant results.

A basic understanding of private keys helps prevent loss of funds and other mishaps, but it can also offer useful insights into how Bitcoin works. This guide outlines the most important private key concepts for effectively using Bitcoin.

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Bitcoin Paper Wallets from Scratch

Paper Wallets

Bitcoin paper wallets offer a useful solution to the problem of storing funds for later use. However, the ease with which paper wallets can be generated tends to obscure important technical and security considerations that may only become apparent at a later point. This article introduces paper wallets from the beginning, with an eye toward using them for secure, long-term, offline storage.

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A Gentle Introduction to Bitcoin Cold Storage

Winter

Imagine opening your Bitcoin wallet. To your surprise, it‘s empty and there’s no way to recover the money you lost. How do you feel?

Every Bitcoin user faces the problem of securely storing their money. Unlike the banking system, there‘s little recourse when things go wrong, and little margin for error. Thefts and losses can be prevented, but they can’t be rolled back. Preventing these losses is the goal of cold storage.

Cold storage is an important subject with a steep learning curve. To make the topic more approachable, this article introduces core Bitcoin concepts when needed. It concludes by discussing a new Bitcoin feature that could simplify the safe storage of funds.

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