Primarily Against A Hash Value In That It Is Easier And Faster To Determine Collisions Based On Two Plaintext Messages Equaling The Same Hash Value Than It Is Trying To Determine The Original Plaintext For A Given Hash Value. This Attack Relies On The Statistical Probability That Two Events Will Happen At The Same Time And That It Will Be Faster To Achieve A Result Using That Method Rather Than Having To Exploit Every Possibility Such As Using Brute Force

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