Analysis of Cryptographic Protection of the Bitcoin Core Cryptographic Wallet

This article discusses the security of implementing encryption for the Bitcoin Core cryptocurrency wallet. Particular attention is paid to aspects of the practical use of cryptographic algorithms when encrypting the wallet.dat file with a password. Practical resistance to brute-force attacks using parallel computing on GPUs is also considered. It is discovered that Bitcoin Core does not implement changing the encryption key for the user's private keys. This implementation makes it possible to carry out a second attack on the wallet without knowing the new password, if it has already been compromised previously. Changes to encryption algorithms are also been proposed to make brute-force attacks more difficult on the GPU.