Modify encrypted text so it decrypts to something else

And the modifications are undetectable by the decrypter!

Here's an example

The message below, Will pay 123456 is encrypted with  'xyz'.

The encrypted text is copied in Corrupted text field for comparison.

Each Modify Corrupted click modifies 2 characters in the Corrupted text.

Click Modify a few times and then Decrypt Corrupted.

Decrypt Corrupted has corrupted text compared to original message.

Change the  Click Encrypt Message and Modify Corrupted.

Same behavior; try it.

Admittedly much of the above is contrieved* –but the important point is

experts can maliciously corrupt encrypted text without leaving a trace!

You can't stop bad actor behavior, but you can identify the attempted fraud using

using Cryptographic fingerprints, next hands-on, prevent this fraud.

*From the excellent book, Beginning Cryptography with Java, by D. Hook