Which exchange shifted to cold storage?

TLDR

Upbit is the exchange that shifted nearly all customer assets to cold storage after a recent security incident, targeting about 99% offline custody to minimize hot?wallet exposure (Upbit cold storage move).

1. Upbit acted after a hack on its Solana hot wallet of about 44.5 billion KRW (~$30 million) (incident background).
2. The plan lifts cold storage to 99%, far above South Koreas 80% minimum requirement (99% target).
3. This reduces online attack surface, but can slow withdrawals during heavy demand (wallet overhaul details).

Deep Dive

1. The Move

Upbit is transitioning to approximately 99% cold storage, cutting hot?wallet exposure to near zero. This is one of the most aggressive custody profiles among major exchanges, intended to protect user funds by keeping them offline and harder to breach (cold storage move).

• As of late October, Upbit already held over 98% of customer assets in cold wallets, and it now aims to reach 99% following its wallet infrastructure review (overhaul details).

2. Why Now

The change follows a targeted exploit on a Solana hot wallet, with losses refined to 44.5 billion KRW (~$30 million). In response, Upbit halted hot?wallet operations, moved assets offline, and pledged to reimburse direct user losses from corporate reserves (hack context).

• South Korea is also considering stricter bank?level liability standards for exchanges, increasing pressure to emphasize security and offline custody ratios (regulatory backdrop).

3. Trade-Offs

Cold storage reduces attack surfaces but adds operational friction. With minimal hot wallets, withdrawals in volatile periods can be slower because moving funds from cold storage often requires extra steps (operational considerations).

Conclusion

Upbits near?total shift to cold storage is a security?first response to a specific hack and a signal of broader tightening in exchange risk management. It materially lowers online attack risk, while creating potential withdrawal friction during market surges. For users, the trade?off is clearer custody safety versus slightly slower access in peak periods.