Real wood furniture infested with pests - what to do?

In dry wood, the pest starves and larvae do not tolerate temperatures of around 60 °C well. However, wood and hot water is probably not the best idea, as the wood may lose its shape. The same can happen with dry heat. Cracks can also form with dry heat. Oak is often infested by the Brown powderpost beetle (Lyctus brunneus). I see two options: 1. the chemical club. However, this is only recommended for slight infestations and for surfaces that do not come into constant physical contact. The substance is drawn up with a syringe and injected into the holes. After some time, a follow-up treatment with wood wax can be applied. 2. call a professional. The professional collects the piece of furniture, packs it in a special device, and fumigates it. Further information can be found on the Internet. :)

Wood and hot water is probably not the best idea, as the wood can lose its shape.

You place a as large as possible closed pot with as much boiled water as possible as a heat reservoir on the affected area. That is neither wet nor dry, only the approx. 60°C in the wood are reached exactly at certain points.

It would be helpful to first determine the extent of the infestation. If the entire (large) piece of furniture is infested, it might be difficult with the pot :)

I am not sure how extensive the infestation is. I only see the wood dust on the shelves, but on both sides of the display cabinet. And in the middle, I see a small hole (middle part between the two sides). I don't think any of it will fit in our small freezer chest. I also don't really see why I should take care of getting rid of the pests. The cabinet is 3 months old, so the seller should take care of it. I am more afraid that the problem will "spread" to surrounding furniture? Is that likely? The piece stands about 5cm from my door frame and about 5cm from another oak solid wood piece of the same series on which I have not found any dust so far. Edit: This is the piece of furniture it is about.

I am rather afraid that the problem might "spread" to the surrounding furniture? Is something like that likely?

Wikipedia helps under "Common furniture beetle." The danger of spreading to other wooden parts exists mainly in the next generation of the little pests, kind of like "We're looking for a nice nest with enough food for our little ones."

I am more afraid that the problem might "spread" to surrounding furniture?

That would be my concern as well. Therefore, I would banish the piece of furniture from the house and return it to the seller / exchange it / have it treated – whatever you agree on together.