The charge, laid by the four umpires on duty, on-field officials Billy Doctrove and Peter Parker, third umpire Rudi Koertzen and fourth umpire Brian Jerling, related to an incident on the first day of the Test, on Friday.
Farhat claimed a catch from batsman Ashwell Prince which was referred to the third official because Doctrove and Parker were unsure whether the batsman had played the ball into the ground or his boot before it reached the fielder.
When Koertzen studied television replays of the incident he noticed the ball had, in fact, not carried to Imran, and when all the umpires had the chance to view the footage at close of play it was decided that a charge should be laid.
But after considering the evidence, ICC match referee Chris Broad decided that Farhat had no case to answer.
"One of the key aspects in favour of the fielder in this instance was that no one questioned the validity of the catch at the time," said Broad.
"It was only when it was referred to the third umpire that it became clear the ball had not carried.
"That ties in with my experience as a cricketer as I know it is possible to believe you have caught the ball when others may have seen it bounce beforehand.
"Bob Woolmer, the Pakistan coach, and team manager Talit Ali appeared at the hearing to vouch for Imran Farhat's good character, and Bob added that during a match in the Caribbean Imran told the umpires he was unsure whether or not a ball had reached him on the full only for replays to show he took the catch cleanly.
"Taking all these factors into account I am satisfied this was simply a case of a genuine and honest mistake by the fielder and so I found him not guilty of the charge," he added.