Base64

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Base 64 is an encoding system. It is very commonly used in capture the flag machines. Messages encoded in base64 consist of letters from a to z, from A to Z and digits from 0 to 9. When encoding, messages are split in groups of 3 characters. If the last group is not 3 characters long, it will be padded with = for groups with two characters and with == for groups with one character, making base 64 strings easy to recognize 66% of the time.

  • We can use Firefox's hackbar to decode base64 easily, or to encode in base64.
  • Always try to decode everything that looks like base64.
  • If there are several strings that look like base64, but individually don't properly decode to ascii, try to combine them, and then decode the different combinations. This happens in Vulnhub's IMF.