Is there any way to decrypt password? (WebCrypto?)

Question

I'm very far from encryption\decryption but recently I faced with such issue:

{"et":"sP8C8QnNiLWk9+dcE9jzHeN+vp28pXq2gB//HancFfB91UxTf6CK4ZCkGobrYkw5","iv":"+++i46W4eYQGYpEP","sb":"N9T1se0OxKX+Ze8q"}

here should be sample encrypted password or phrase, it is known that it was encrypted with WebCrypto. But all decryption examples are represent phrase as base64 and salt/iv as hex. May be exist function to convert it to hex in right way, or may be there is no way to decrypt this one with data above?

Answer 1

Base64 and Hex are just different ways of representing raw bytes of data. They are trivially converted between. For example, the IV is currently in Base64. If you wan to convert that to Hex, on most unix-like systems you can use base64 and xxd:

$ echo +++i46W4eYQGYpEP | base64 -D | xxd -p
fbefa2e3a5b879840662910f

That said, I'm not familiar with this particular format. Most encryption formats are ad hoc and don't follow any particular standard. In order to build a decryptor, you need to know the precise implementation details of the encryptor. Just looking around for "AES decryptor example" will not help you much here. Besides obviously needing to know the key, you need to know the algorithm, the mode, the padding scheme, and several other considerations if a salt is involved (I'm not clear what "sb" is here).

"Encrypted with WebCrypto" is not sufficient information. The first, most obvious question is: what is the encryption key? If you don't have that, then no, this is not decryptable. Once you have the key, you should get the code that generated this output, and write a decryptor that does each step in reverse.