Syscoin (SYS)

Syscoin released a technical post‑mortem stating that on June 7, its UTXO-to-NEVM cross-chain bridge was subjected to a malicious UTXO burn transaction that created asset identification ambiguity, causing the bridge contract on the NEVM side to erroneously release 5 billion native SYS. The vulnerability stemmed from inconsistent cross‑layer interpretation of the same transaction between Syscoin Core and the NEVM relayer: Core could interpret it as an attacker‑custom asset, while the relayer interpreted it as native SYS.

Syscoin said that after the team tracked the fund flow and contacted the attacker via on‑chain information, the 5 billion SYS have been returned to the official recovery address and subsequently burned through a standard OP_RETURN transaction, making them unspendable by the protocol, and restoring supply to the intended level. The bridge remains paused, and the team has fixed the relayer logic to reject multi‑asset, duplicate‑asset commitments or any burn proof with unclear asset identity. https://t.co/WEGHTwmfwc

Syscoin, stolen SYS tokens confirmed returned to recovery address.

https://t.co/TygJgbehX2 https://t.co/dCmscRCVTi