Question 1

What caused the Syscoin bridge exploit?

Accepted Answer

The attacker crafted a UTXO burn transaction with two asset commitments targeting the same output, exploiting the fact that Syscoin Core and the NEVM relay interpreted the ambiguous payload differently, according to Syscoin's technical postmortem published June 15, 2026.

Question 2

Were the exploited SYS tokens recovered?

Accepted Answer

Yes. The attacker returned all 5 billion SYS to a designated recovery address after the Syscoin team traced the funds and made on-chain contact. The tokens were then permanently destroyed via an OP_RETURN burn transaction viewable on Syscoin's block explorer.

Question 3

Is the Syscoin bridge operational again?

Accepted Answer

No. As of Syscoin's June 15 postmortem, the bridge remains paused while the team completes final review and validation of its fix. Native SYS deposits at exchanges have resumed, but cross-chain bridge transfers are still closed.

SYS

Syscoin recovers and burns 5 billion hack tokens

One sharp brief.
Every day.

SYS

Syscoin recovers and burns 5 billion hack tokens

One sharp brief.Every day.

One sharp brief.
Every day.