South Korea’s National Tax Service accidentally leaked a crypto wallet seed phrase in an official press release, leading to the theft of 4 million PRTG tokens worth roughly $4.8 million. The incident is part of a series of crypto custody failures testing South Korean authorities, including a separate police case where 22 Bitcoin vanished from a vault.
South Korea’s National Tax Service exposed a wallet seed phrase in a press release on Thursday, leading to a significant theft. Local media reported the release included an unmasked image of a mnemonic phrase related to a tax enforcement campaign.
Blockchain researchers identified an Ether address linked to the leaked phrase. Onchain data shows the address received then sent out 4 million PRTG tokens.
Associate professor Jaewoo Cho of Hansung University’s Blockchain Research Center confirmed the theft. “We have confirmed that 4 million PRTG tokens, worth approximately $4.8 million, were stolen from the mnemonic that was leaked,” he stated.
Cho noted the other exposed mnemonics seemed less problematic. He added that the stolen tokens were difficult to cash out, making the actual damage negligible.
This incident occurs amidst other crypto custody scandals in South Korea. Police discovered in February 2026 that 22 Bitcoin seized in a 2021 case had vanished from a police vault.
Two suspects were arrested after investigators found the coins were moved using a mnemonic phrase police never controlled. Separately, regulators face pressure over Bithumb’s recent promotion error involving $43 billion in non-existent Bitcoin.
