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cryptography/aes-cbc-poa/DESCRIPTION.md

@@ -15,7 +15,14 @@ This is called a [_Padding Oracle Attack_](https://en.wikipedia.org/wiki/Padding
 
 Of course, once you remove (and learn) the last byte of the plaintext, the second-to-last byte becomes the last byte, and you can attack it!
 And when you recover the entire last block, you can simply discard it, making the second-to-last block the last block.
-You'll need to slightly adjust this attack for the 16th byte of a block, since there is not padding at all, but I trust in your ability to do so!
 
 So, what are you waiting for?
 Go recover the flag!
+
+----
+**HINT:**
+You'll need to slightly adjust this attack for the 16th byte of a block, since there is no padding at all initially, but I trust in your ability to do so!
+
+**FUN FACT:**
+The only way to prevent a Padding Oracle Attack is to avoid having a Padding Oracle.
+Depending on the application, this can be surprisingly tricky: a failure state is hard to mask completely from the user/attacker of the application, and for some applications, the padding failure is the only source of an error state!