ChainBleedv0.1 · open intel
← back to feed·BSCFLASHLOAN2021-08-17 · 4y ago
Incident · SLOWMIST

XSURGE

Flash loan attack
Estimated loss
$5.00M
VERDICT —UNRATED
Verdict pending. Auto-ingested incidents are reviewed before a public verdict is rendered.
▰ METHOD
FLASHLOAN
FLASHLOANBYTECODE CATCHABLEAI SCANNABLE
Root cause

Root-cause analysis not yet published. The incident description below contains all currently available signal — review the attack transaction directly for definitive forensics.

▰ PROOF OF CONCEPT
DEFIHACKLABS
src/test/2021-08/XSURGE_exp.sol
view forked test on github ↗

Reproducible Foundry test fork from SunWeb3Sec/DeFiHackLabs. Clone the repo, run forge test against the file path above, and replay the exploit against a mainnet fork at the historical block. Use for reproduction only — not for live targets.

Forensic narrative

On August 17, the DeFi project XSURGE on BSC suffered a lightning loan attack. On August 16, local time, XSURGE officially issued a statement about the SurgeBNB vulnerability before the attack. Since the SurgeBNB contract cannot be changed and has been abandoned, the vulnerability cannot be patched. XSURGE said that it did not disclose any specific details about the nature of this vulnerability, but strongly recommends that users migrate out of SurgereBnb as soon as possible. The vulnerability may be triggered by an attacker at any time. After the announcement, XSURGE was subsequently attacked, and the attacker stole $5 million from SurgeBNB. Attack method (per SlowMist): Flash loan attack. Reported loss: $ 5,000,000.

Primary source
https://twitter.com/XSURGEDEFI/status/1427359459102404609
Sourced from
slowmist
Technical record
chain
bsc
protocol
XSURGE
bug_class
flashloan
date_occurred
2021-08-17
loss_usd
$5,000,000
source_id
sm:xsurge::2021-08-17
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