In the most recent custody blunder for the authorities, the National Tax Service of South Korea reportedly published a wallet seed phrase in a press release. The result was a rapid depletion of tokens valued at $4.8 million.
According to local news reports, the National Tax Service (NTS) of South Korea unintentionally revealed a crypto wallet seed phrase in an official press statement on Thursday. This caused the address to lose 4 million PRTG (Pre-Retogeum) tokens valued at roughly $4.8 million.
Source: Naver
4 Million PRTG tokens drained after press release error
Several Korean news sites, including Naver and Chosun, have reported that the press release was about the National Tax Service’s campaign to catch tax evaders and seize their assets. The release is said to have had a picture of a Ledger cold wallet and a piece of paper with the wallet’s full mnemonic phrase on it, with no blur or masking.
Later, blockchain experts found an Ether (ETH) $1,947 address that was connected to the leaked phrase. This address momentarily held the 4 million PRTG tokens before the whole balance was moved out.
Onchain data for that address indicates three incoming transfers of 4 million PRTG each, followed by one outgoing transfer of 4 million PRTG to another wallet, which fits with those reports.
Jaewoo Cho, an associate professor at Hansung University’s Blockchain Research Center, looked at the flows and said on X on Friday, We have confirmed that 4 Million PRTG tokens, worth about $4.8 million, were stolen from the mnemonic that was disclosed through a press release from the National Tax Service.
Other exposed mnemonics don’t seem likely to cause any major problems,” and he said that “the actual damage is at a negligible level” because it was difficult to cash out the stolen tokens.
He expressed his belief that the event could serve as a hidden opportunity for Korean government agencies to improve their procedures for managing virtual assets.
Missing seized Bitcoin and exchange errors
This occurrence happens at the same time that South Korean officials are dealing with another crypto custody controversy. In another case, authorities found out in February 2026 that 22 Bitcoin (BTC $66,049) that had been taken during a hacking investigation in 2021 had disappeared from a cold wallet kept in a Gangnam police vault.
On Thursday, police detained two people after finding out that the coins had been moved using a mnemonic phrase that the authorities had never been able to manage.
Regulators are also under pressure because of Bithumb’s recent mistake with the 620,000 BTC fat finger promotion, which briefly gave users about $43 billion in fake Bitcoin. After receiving criticism for not identifying serious system flaws sooner, the Financial Services Commission has also extended its investigation.