How can I decrypt a string and get the algorithm used for the encryption

Question

I want to know how to decrypt a text without knowing the key used or the algorithm such as this text:

RUE2RDRDMDE5OTpxci1hZG1pbi1yZWFkZXIxOjAwMDdDMUJBOEU4Q0IyOUQwNjg1RkJDRkMzMDdDMjc4:Nzg0MTk5MDUzMjA1OTEyXzk3MTUwODkzODk1MjpuY2hjNnkzenFkb2tvZXR0cWR2OTo2OEJFNkFCMTY4RjNGMTdFNUJFRjY3OTgwQjgwMDBTRVZBQURZRUVSVUFBTDBBTUtGdFM2QVNIQUwwRUE=

does this text has any signs that could help me to know at least what is the algorithm used? and then how to decrypt without knowing the key?

First: your "code" is just a Base64 encoded string (see answer from @Ritzga). Second: before and after the header ("qr-admin-reader1") you find some values - some of them might be hex encoded values. With the given parameters (or better NO parameters) it is like searching of a needle in a hay stack (or brute forcing over lots of algorithms, key derivations, encoding ...) to find a decryption algorithm. The most easiest solution would be: ask the one who created the QR-code were the data is taken from. I'm voting this question as it has nothing to do with a programming problem, sorry. — Michael Fehr, Jun 22 '21 at 21:06

score 2 · Accepted Answer · answered Jun 22 '21 at 20:24

2

This is base64 encrypted there are no key needed for this. But in general, you can test all possible encryption algorithms and look at all the results.

Decoded: EA6D4C0199:qr-admin-reader1:0007C1BA8E8CB29D0685FBCFC307C278784199053205912_971508938952:nchc6y3zqdokoettqdv9:68BE6AB168F3F17E5BEF67980B8000SEVAADYEERUAAL0AMKFtS6ASHAL0EA

answered Jun 22 '21 at 20:24

Ritzga

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How to get the real data then ? – Student. Engineering Jun 22 '21 at 20:27
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What do you mean by 'real data' ? I mean you can try all encoding algorithms (eg. this list https://en.wikipedia.org/wiki/Binary-to-text_encoding) and after this you could try encryption algorithms with guessing the key. – Ritzga Jun 22 '21 at 20:37
I want to know the text in the decoded result as the numbers not encrypted only the letters ... – Student. Engineering Jun 22 '21 at 21:03
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Try all the algorithms with all of the keys. Seriously - that's the **POINT** of encryption – symcbean Jun 22 '21 at 23:01

How can I decrypt a string and get the algorithm used for the encryption

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