webmedium

Купоны64 (Kupony64)

hackerlab

Task: Coupon validation system with blacklisted 100% discount coupon. Solution: Bypass Base64 blacklist filter by injecting whitespace (newline) into the encoded string, which the decoder ignores but the filter does not recognize.

$ ls tags/ techniques/
Base64 whitespace injection to bypass blacklist filterPattern recognition in coupon formatFilter evasion via newline character injection

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