SHA256 is used for mining but that would only expose new coins that are being generated. If there was a vulnerability there the community would switch to a new mining algorithm to secure new blocks.
Addresses are protected by hashing a public key to the bitcoin address (https://en.bitcoin.it/wiki/Technical_background_of_version_1...). If you've always sent coins to new addresses like the hierarchical deterministic wallets do then your public key is only exposed after you spend the coins, so you are not susceptible to a cracking attempt on the public key.
Addresses are protected by hashing a public key to the bitcoin address (https://en.bitcoin.it/wiki/Technical_background_of_version_1...). If you've always sent coins to new addresses like the hierarchical deterministic wallets do then your public key is only exposed after you spend the coins, so you are not susceptible to a cracking attempt on the public key.