Last week, Rivian Automotive (RIVN 6.10%) unveiled not one, but two new prospective electric vehicles: The slimmed-down R2 electric SUV and an unexpected R3 electric hatchback. But investor beware: On Monday morning, investment bank UBS warned investors that not all is well with Rivian.

Despite raising its price target a bit to account for the potential gains of having two new vehicles to sell, UBS nonetheless retained its sell rating on Rivian stock and set a price target of $9, which would be 27% below its price on Tuesday morning.

Is Rivian Automotive stock a sell?

UBS is not a total Rivian bear. To the contrary, in its note covered on TheFly.com Monday morning, the Swiss banker praised Rivian's decision to postpone construction of a new factory in Georgia, and begin building its new R2 EV at its existing plant in Normal, Ill., instead. UBS observed that this move will save Rivian more than $2.25 billion (well, until it ends up spending the $2.25 billion anyway, and eventually builds the Georgia plant).

Still, the banker is pleased to see Rivian being a bit more careful about how quickly it spends its cash, after burning through nearly $10 billion of its $18.1 billion in IPO cash in just two years. Rivian's new R2 still won't begin production until the first half of 2026, however, meaning Rivian must make its remaining $9.4 billion last two more years.

Even if Rivian holds its existing level of cash burn flat, however, I don't see how the company can accomplish that -- and UBS has concerns as well. The analyst predicts Rivian will need to sell more shares to raise more cash to bring R2 to market, and the logical time to do that would be now, when its stock price is flying high. Of course, more shares sold would mean less ownership interest in Rivian per share that investors own today. Essentially, the stock would be chopped up into more pieces -- and each of those pieces would logically be worth less.

If that's the scenario investors have to look forward to, it makes sense that Rivian's shares would fall in value -- perhaps even to $9 each.