Hack history / 2021 / Hack or exploit
XDX Swap
Hack or exploit on Jul 2, 2021 · Bridge Logic Flaw
SOURCES AGREE ON DATE AND LOSS · 2 SOURCES
Lost
$176K
dollars at the time
Returned
none listed
as the sources state it
Rank
#1,531
among thefts by dollars lost
What happened
On July 2, 2021, XDX Swap on the HECO chain was exploited via a suspected backdoor in the cross-chain decentralized exchange code, allowing an attacker to extract approximately $176K (85.17 ETH). Most funds were subsequently recovered with support from Star Labs and the HECO White Hat Security Alliance.
Details
- Date
- Jul 2, 2021
- Kind
- Hack or exploit
- Method
- Bridge Logic Flaw
- How in
- Bridge and cross-chain
- Target
- DeFi protocol
- Chains
- Huobi Eco Chain, HECO
After the theft
- Recovered or seized
- yes, amount not stated
“Most funds were subsequently recovered with support from Star Labs and the HECO White Hat Security Alliance.” (DefiLlama)
Reported by
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Cite this page
SwanBluechip, "XDX Swap hack, Jul 2, 2021: $176K lost", Crypto hack history, https://swan-hack-tracker.pages.dev/history/i/htbee55eeebc/ (data as of 2026-10-31).