Oh Kyung-seok, CEO of South Korean cryptocurrency exchange UPBIT, issued a statement on Friday disclosing a serious security vulnerability discovered in its internal wallet system during an urgent investigation into the $30 million theft that occurred earlier this week. UPBIT stated that the vulnerability could have allowed anyone analyzing publicly visible UPBIT on-chain wallet transactions to deduce the private key, the cryptographic credential controlling access to funds. This suggests a possible flaw in UPBIT's own wallet software, producing weak or predictable signature data that could allow attackers to mathematically reconstruct the private key. UPBIT did not directly link this vulnerability to the attack, stating that the issue was discovered and resolved during a comprehensive system check following the discovery of unusual withdrawals from its Solana-related wallets on November 27. (TheBlock)