There's some rubles in there.

[Ostap]

The oligarchs own s**t everywhere. Real estate in New York -- oligarch money. Sports teams in Britain -- oligarch money. That couch you're sitting on right now. Well, I mean, you bought that, but... check between the cushions. There's some rubles in there.
link with timecode The Daily Show with Trevor Noah

Hello, everyone. I understand the literal meaning of the sentence, but, what did he mean by that?

 

[Skrej]

It's not uncommon to find loose change in one's sofa cushions, amongst other stuff. 'Rubles' being of course the Russian currency thus makes it a metaphor for Russian involvement in something even as commonplace as furniture.

 

[Ostap]

Hmmm... It looks like a weak joke, since sofas are not exactly luxury items.

 

[Skrej]

That's the intended joke - that these oligarchs have their hands on even low-end consumer products.

It's an example of hyperbole - exaggeration to highlight the expressed sentiment.

I suppose you could even read into it a suggestion of money-laundering.

 

[Tdol]

It suggests that the money from these oligarchs has permeated society at all levels. It's comedy rather than an accurate analysis of the economic effect, though the effects were very significant.