The KOSPI Index is in the news due to a significant jump following a wild circuit breaker session. According to the article, the KOSPI Index experienced a notable increase after the session. The article does not provide specific details about the circuit breaker session, such as the exact events that triggered the session or the duration of the session. However, it mentions that the session was wild, indicating that it was likely volatile and unpredictable. The article does not provide information on the specific factors that contributed to the jump in the KOSPI Index. It only mentions that the index jumped after the session, without providing further context or analysis.