Key facts
- Wanchain bridge connecting Cardano and BNB Chain exploited on July 21, 2026.
- Approximately 515 million NIGHT tokens worth $13 million were drained.
- The exploit was due to a signature reuse flaw in the TreasuryCheck validator.
- The NIGHT token price dropped over 30% following the hack.
- The Midnight Foundation confirmed its network and Cardano remain secure.
On July 21, 2026, a significant exploit targeted the Wanchain-operated bridge facilitating connections between Cardano and BNB Chain. Attackers successfully drained approximately 515 million NIGHT tokens, valued at around $13 million, from the bridge's treasury. This event triggered a sharp decline in the NIGHT token's price, which fell by over 30% to a new low of approximately $0.016.
Wanchain has since taken the affected bridge offline and is actively investigating the incident. On-chain security analysis firm BlockSec Phalcon pinpointed the vulnerability to a flaw in the TreasuryCheck validator, specifically a non-injective signed-message encoding that allowed for signature reuse. This allowed the attacker to inflate the token supply by an estimated 65,000 times in a single transaction by manipulating field boundaries.
The Midnight Foundation was quick to issue a statement clarifying that the exploit was isolated to the third-party bridge infrastructure and did not impact the security or integrity of the Midnight network, its validators, consensus mechanism, or core protocol. Similarly, the Cardano network itself remained unaffected. The stolen tokens were dumped on decentralized exchanges, contributing to the price collapse.
This incident underscores the persistent risks associated with cross-chain bridge infrastructure. While the Wanchain bridge experienced a breach, the underlying Midnight protocol and Cardano ecosystem remain robust. The exploit affected roughly 2% of NIGHT's total supply, originating from the bridge treasury rather than the circulating supply, a distinction that analysts note is crucial for investor perception.