Seized Crypto Stolen As South Korea’s Tax Authority Leaks Private Key

A piece of paper ruined everything. South Korea’s National Tax Service (NTS) published an official press release last Thursday meant to highlight its crackdown on tax dodgers — and somewhere in the process, a full wallet seed phrase was photographed, printed, and sent out to the public without anyone apparently noticing.

By the time someone did, $4.8 million worth of tokens had already walked out the door.

One Photo, One Mistake, Millions Gone

The press release included an image of a Ledger hardware wallet placed next to a handwritten sheet containing the wallet’s complete mnemonic phrase — the string of words that functions as the master key to any crypto wallet.

No blurring. No masking. Nothing. According to reports from Korean media outlets including Naver and Chosun, the release was part of a broader NTS enforcement campaign targeting people who owed taxes, with seized crypto assets shown as evidence of the agency’s work.

What was meant to showcase government action instead handed anyone with sharp eyes full access to the funds inside.

Blockchain researchers who examined the wallet’s transaction history found three separate incoming transfers totaling 4 million PRTG (Pre-Retogeum) tokens, followed by a single outgoing transfer that swept the entire balance to another address. Clean. Quick. Gone.

Researcher Says Actual Losses May Be Smaller Than They Appear

Associate professor Jaewoo Cho of Hansung University’s Blockchain Research Center confirmed the theft publicly on X, writing that the 4 million tokens — valued at roughly $4.8 million — were taken directly from the mnemonic phrase exposed in the NTS release.

He also examined other wallets whose seed phrases may have been visible in the same image and said those did not appear to carry significant risk.

Cho added that because PRTG tokens are hard to convert into cash, the real financial damage could be far smaller than the headline number suggests. He expressed hope that the incident would push South Korean government agencies to finally build proper systems for holding seized crypto assets.

The NTS has not issued a public response to the incident as of this writing.

What makes this story harder to ignore is that it did not happen in isolation. Reports say South Korean police separately discovered in February 2026 that 22 Bitcoin seized during a 2021 hacking case had gone missing from a cold wallet kept inside a Gangnam police station vault.

Two suspects were arrested after investigators determined the coins had been moved using a mnemonic phrase that authorities had never held control over.

The coins, worth roughly $1.4 million, are gone.

Featured image from Unsplash, chart from TradingView