Low Smart contract exploit Source: SlowMist Hacked

Nimiq hacked

An attacker exploited an OpenGSN meta-transaction authorization flaw on Polygon HTLC contracts, allowing them to lock and redeem stablecoins worth approximately $50,463. The attacker used leftover ERC-20 allowances to move USDC, USDT0, and USDC.e into HTLCs and then redeemed them.

Estimated loss
$50,463
Protocols
Nimiq
Chains
Polygon
Confidence
High
First seen
18 Sep 2026, 10:00 UTC

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