Authenticate a user by a given password and salt without knowing the encryption method

Question

Story I'm using SQL Server database, and there is a table called aspnet_Membership that it seems like it's generated by ASP.NET. The system's frontend no longer uses ASP.NET but still would like to authenticate users from the old database. What I know The Password and PasswordSalt columns in the table I think are essential to authenticate a user, however, I don't know what encryption method was used in the system. An example of a password looks like this: K9YjVGWxF4bPQCvQ8VYA1vbQyCE= and password salt looks like this: CM9k+UbZuKTuFxI46vIVIA==. There is also a PasswordAnswer field that it seems like it uses the same encryption method, but I don't think it would matter in terms of authenticating a user. Question How can I authenticate a user by the given password and salt (ExpressJS preferably)? Thanks JavaScript questions and answers, JavaScript questions pdf, JavaScript question bank, JavaScript questions and answers pdf, mcq on JavaScript pdf, JavaScript questions and solutions, JavaScript mcq Test , Interview JavaScript questions, JavaScript Questions for Interview, JavaScript MCQ (Multiple Choice Questions)

Answer 1

You will need to find the method which is being used for logging in. In order to do that, open your web-browser, go to the main page of your application, open dev console and view the Network tab. Then log in, see where the request is going, analyse the code and find the method which authenticates your login. Another way to find that method is to search for the usages of the Password field of the ORM used (if an ORM is being used) and finding where it is being stored at registration or settings edit, or when it is being authenticated at login. If this fails as well, then search for the word of password in the entire source-code and see whether you find the authentication of password or the way the password is stored. If this fails as well, search for the word of salt in the source-code and see if you find any useful results. If this fails, then search for words like login or authenticate in your source-code. And if all these fail, you will need to either get creative in your search or ask someone in the team who knows the answer. When you find a method which takes a String as input for password and generates another String as output and checks it against your password and salt, then you found your method. Once you find your method, you will just need to ensure that you use it in your project or implement a similar way to authenticate users.