CBC padding attack

RootMe Challenge: Don’t go too fast: Find the validation flag located in the following encrypted message:

BC16542433100D9522DC3B6428D4FF5F7FC67B4994323C47ED09F185C3CE7A2E

• The Padding Oracle Attack, by Robert Heaton

• Padding oracle attacks on the ISO CBC mode encryption standard

• Security flaws induced by CBC padding

• Efficient padding oracle attacks on cryptographic systems

• Practical Padding oracle attacks