Upbit, Bithumb, and Coinone, three major South Korean cryptocurrency exchanges, have jointly designated Quiztok (QTCON) as an investment caution item, signaling potential risks to investors. This decision stems from a recent security incident affecting QTCON's virtual asset wallet or distributed ledger. Upbit explicitly stated that the incident involved hacking activities related to the issuance, transfer, or storage of QTCON. Crucially, the exchange highlighted that the root cause of the breach remains unidentified and unresolved. Furthermore, the exchanges criticized the delayed disclosure of the security incident. The lack of timely communication through appropriate channels raised concerns about transparency and investor protection. Investors are advised to exercise caution and conduct thorough research before engaging with QTCON. While further details are awaited, this designation underscores the importance of security and transparency within the cryptocurrency market. ```