Buran (Snowstorm in Russian) is a Soviet Reusable spaceplane apart of the Buran programme. It has the capability to dock to a station (possibly in LEO) and use its 2 OMS thrusters to get into LLO (Low Lunar Orbit). The Buran was launched on the Energia (EN-ERR-GEY-UH) Super Heavy Lift launch vehicle.
IRL, Buran only had one flight in 1988. The Buran, in For All Mankind can be modified to host weapons, on the two sides of the cargo bay (Not on the doors).
In LLO, Buran and Pathfinder have a standoff. Pathfinder fires two missiles at Buran, but Pathfinder diverts to Sea Dragon 17.