CVE-2025-59942: go-f3 module vulnerable to integer overflow leading to panic

Filecoin nodes consuming F3 messages are vulnerable. go-f3 panics when it validates a “poison” messages. A “poison” message can can cause integer overflow in the signer index validation. In Lotus’ case, the whole node will crash.

There is no barrier to entry. An attacker doesn’t need any power to pull off this attack.

These malicious messages aren’t self-propagating since the bug is in the validator. An attacker needs to directly send the message to all targets.