Steyn had been asked by the IPL to clarify why elevated levels of morphine were found during a random drugs test while he was playing for the Bangalore Royal Challengers in the Twenty20 competition in April.
Steyn blamed the medication he took for migraines for the irregular findings.
"There was a discrepancy in the result of a doping test during the IPL but the authorities are perfectly satisfied with the explanation that Dale has provided and they have confirmed that no offence has been committed," CSA chief executive Gerald Majola said in a statement released on Wednesday.
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