**Known Bug in Libbitcoin Explorer (bx) 3.x Puts Over 120,000 Bitcoin Wallets at Risk**

A critical vulnerability discovered in the Libbitcoin Explorer (bx) 3.x library has exposed more than 120,000 Bitcoin (BTC) wallets worldwide to potential hacking attempts. The issue stems from a weak random number generation method, making it significantly easier for attackers to guess seed phrases and compromise wallet security.

### Thousands of Bitcoin Wallets Vulnerable to Brute Force Attacks

First identified in November 2023, this vulnerability continues to leave non-custodial Bitcoin wallets susceptible to brute force attacks. On October 17, 2025, the OneKey wallet team shared an overview of the potential attack vector involving the vulnerable library.

The Libbitcoin Explorer (bx) library—a software development toolkit used to build Bitcoin wallets in C++—uses the Mersenne Twister-32 algorithm for random number generation. However, this algorithm was seeded solely with the system time, limiting the seed space to just 2³² possible values. This restricted seed space considerably weakens wallet security, making it easier for attackers to enumerate potential seeds.

As a result, wallets generated with certain versions of Trust Wallet and directly through Libbitcoin Explorer (bx) 3.x can be recovered by malicious actors.

### How Does the Hack Work?

Because the seed space is so small, a high-performance personal computer can exhaustively enumerate all possible seeds within days. This capability allows attackers to predict private keys generated at specific times, enabling them to steal assets on a massive scale.

Despite this weakness in the random number generator (RNG) being publicly known for over two years, many Bitcoin users relying on affected wallets still face significant risks.

### Three Steps to Protect Your Funds

To safeguard your Bitcoin holdings, users with non-custodial wallets created using vulnerable tools between 2017 and 2023 should take the following precautionary measures:

1. **Move Funds to Secure Wallets**
Transfer your assets to wallets protected by Cryptographically Secure Pseudo-Random Number Generators (CSPRNG) to ensure stronger randomness and security.

2. **Generate New Seed Phrases Using BIP 39 Standards**
Creating new seed phrases based on the BIP 39 specification can add an essential security layer to your Bitcoin wallet.

3. **Audit All Paper and Hardware Wallets**
Review any physical wallets that may be affected by the vulnerability, known in the community as the “Milk Sad Case,” and replace them if necessary.

For software wallet users, always keep your wallet applications and operating systems updated to the latest versions to minimize the risk of exploits.

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By following these steps, Bitcoin users can reduce the risk of falling victim to brute force attacks targeting wallets generated with the flawed Libbitcoin Explorer (bx) 3.x library. Staying informed and proactive is essential in protecting your digital assets.
https://u.today/120000-bitcoin-btc-wallets-at-risk-with-this-vulnerability