It's absolutely not legal to immediately sell an asset gained via civil judicial forfeiture for personal gain.
It's a legal action filed against the property itself because they believe it was involved in a crime or purchasing with proceeds from a crime. It's basically charging the asset with a crime.
The state can sell the property, but only if no one has filed a claim contesting the seizure for a period of time. There are strict time limits and notification requirements before this can be done.