Before Spring Security 5, the framework allowed only one PasswordEncoder throughout the application and also had weak password encoders such as MD5 and SHA. These encoders also didn't have dynamic salt, rather it had more static salt which had to be supplied. With Spring Security 5, there have been huge changes in this area and with the new version, the password encoding concept employs delegation and allows multiple password encoding within the same application. The password which has been encoded has a identifier prefixed to indicate what algorithm has been used (see the following example):
{bcrypt}$2y$10$zsUaFDpkjg01.JVipZhtFeOHpC2/LCH3yx6aNJpTNDOA8zDqhzgR6
This approach enables multiple encoding as needed within the application to be employed. If no identifier is mentioned, this means it uses the default encoder, which is StandardPasswordEncoder.
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