Upbit, Bithumb and two other Korean exchanges to delist Zilliqa (ZIL) on Nov. 16

Zilliqa (ZIL) will stop trading on four South Korean exchanges with won markets — Upbit, Bithumb, Coinone and Digital X (formerly Korbit) — at 3 p.m. KST on Nov. 16. The four exchanges announced the end of trading support on the afternoon of Oct. 16, three months after ZIL was flagged following the theft of ZIL from an exchange's cold wallet in July.

From a cold wallet theft to a Ledger app flaw

Zilliqa's team said on its official X account on July 20 that it had been made aware of "a security incident involving one of our exchange partners, in which ZIL was stolen from a cold wallet." A cold wallet is one kept offline, away from the internet. Zilliqa asked all exchanges to pause ZIL deposits and withdrawals for the time being and did not disclose the size of the theft or the exchange involved. The post went up at 7:17 p.m. KST, but Korean exchanges had already halted ZIL deposits and withdrawals before then: Korbit (now Digital X), Upbit (7 p.m.) and Coinone (7:05 p.m.). Upbit cited signs of a security incident at a specific exchange.

Two days later, on July 22, Zilliqa disclosed a flaw in its app for Ledger hardware wallets. It did not say whether the exchange theft was linked to the flaw. The app, it said, had always filled the top 64 bits of the random number (nonce) used to create signatures with zeros, a bug present in every version since 2019. Accounts that signed roughly five or more native Zilliqa transactions with the app could have their private keys recovered from signatures already public on the blockchain and "should be considered compromised," it said. Zilliqa halted native transactions to prevent further losses and said transactions in the Ethereum-compatible (EVM) format were not affected. Overseas exchange KuCoin helped identify the flaw.

After three months of review, exchanges say the reasons remain unresolved

Upbit and Coinone designated ZIL as an investment caution asset on July 22, citing a security incident such as a hack on the wallet or distributed ledger whose cause had not been identified or fixed. Upbit extended the designation twice, on Aug. 21 and Sept. 18, to further review Zilliqa's explanations and remedial measures.

Upbit said it "determined that the reasons for the designation have not been resolved," and Bithumb said "the foundation's explanatory materials alone did not resolve the reasons for the caution designation." Coinone said it found no materials showing the reasons had been resolved. Digital X also announced the end of trading support that afternoon. On Upbit, both the Korean won market (ZIL/KRW) and the bitcoin market (ZIL/BTC) will close. On the same day, Bithumb and Coinone extended the caution designation for MANTRA.

Withdrawals open until 3 p.m. on Dec. 16

Withdrawing gets harder after the deadline. Coinone said users can still request withdrawals through its customer center after support ends, but fees may apply. Upbit said it will not support airdrops, wallet upgrades or hard forks for ZIL after this notice.

ZIL slides 28% on Upbit within 30 minutes of the notice

On Upbit, ZIL stood at 4.59 won at 4:30 p.m. KST, when the notice was posted, and fell to 3.32 won within 30 minutes, a drop of about 28%. It later recovered some of the losses and traded at 3.57 won as of 8:30 p.m. on Oct. 16, 18.7% below the previous day's close of 4.39 won. Its 24-hour trading value swelled to 10.1 billion won. At the same time, it traded at 3.578 won on Bithumb.

On Binance, ZIL traded at 0.00267 USDT, down 15.1% over 24 hours. Converted at Upbit's tether price of 1,344 won, that is about 3.59 won, roughly in line with Korean prices. ZIL's one-year high on Upbit was 12.5 won on Oct. 19 last year, and its low was 2.84 won on Aug. 12 this year, after the theft.