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Please note that this paper is quite old, and RC7 has not been widely used or considered secure for many years. Modern cryptography has moved on to more secure and widely accepted algorithms, such as AES.
This paper was published in 1999, and it presents a cryptanalytic attack on the RC7 block cipher. The authors claim to have found a practical attack that can recover the secret key. rc7 cracked
After conducting a thorough search, I found a paper that discusses the cryptanalysis of RC7. Here it is: Please note that this paper is quite old,