In practice, no. In theory, also no.
The Universe is filled with photons with an energy distribution corresponding to $2.73\,\mathrm{K}$, called the cosmic microwave background (CMB). Every $\mathrm{cm}^3$ of space holds around 400 of them, so each second one $\mathrm{cm}^2$ is hit by roughly one hundred billion of these photons. That means that if you place your "stable body" in an ever-so-isolated box, the box itself will never come below $2.73\,\mathrm{K}$, and neither will the body inside. It will asymptotically go towards thermal equilibrium at $T = 2.73\,\mathrm{K}$.
Even if you magically removed everything else in the Universe but the body$^\dagger$, $0\,\mathrm{K}$ can never be reached. The reason is that this would imply zero motion of the atoms of the body, which is forbidden by law.
In practice, it is actually possible to have temperatures lower than the 2.73 K of the CMB. When a gas expands, it cools, and if it expands faster than it can be heated by the CMB, it can temporarily reach lower temperatures. This is the case for the Boomerang Nebula, which has a temperature of 1 K. The nebula will probably be heated to the temperature of the CMB in around 10,000 years or so.
$^\dagger$Or waited billions of years for the CMB to cool.
Since boiling, by definition, occurs when a liquid's vapor pressure reaches ambient pressure, your question is identical to asking what the vapor pressure of water is at room temperature. Here's an example of an online table:
At 23°C, for example, water would boil at a pressure of about 21.1 torr, or about a fortieth of atmospheric pressure.
Best Answer
There is no such thing as perfectly isolated cryogenic tank. Some heat will always transfer to the contents. However, cryogenic liquid tanks are not completely sealed. They instead have pressure relief valves. The valve opens when the internal pressure exceeds some upper limit, then closes when the pressure drops below some lower limit. This is the mechanism by which cryogenic liquid tanks (including liquid nitrogen tanks) stay cold.
Suppose a full liquid nitrogen tank is abandoned for decades. What happens over time won't be very exciting. A decade later, the tank pressure will be somewhere between the relief valve's upper and lower pressure limits, the temperature will be very close to ambient, and the mass of nitrogen in the tank will be very small. Almost all of the nitrogen will have boiled off and been vented to the atmosphere.
Now suppose the tank is abandoned and the relief valve fails in the closed position. What happens in the ensuing decades will briefly be exciting. Something will fail, catastrophically. It might be the relief valve, it might be some other valve, or it might be the tank itself. The end result will be an empty tank (or perhaps an empty remnant of a tank).
Finally, let's suppose the tank has no valves and is incredibly strong. For lack of better words, it's made of unobtainium. (But not Thermodynamically Isolated Unobtainium©; that stuff is ridiculously expensive.) After decades of abandonment, the contents of the tank will be at ambient temperature and at a ridiculously high pressure. The contents won't be a liquid (nitrogen's critical temperature is -146.9 °C), but it won't quite be a gas, either. The reactions of a highly pressurized supercritical fluid are somewhere in between those of things we call liquids and things we call gases.