There’s a small re-texture that gives Soviet infantry body armor, thus making them the Assault Group troops.
Texture was reworked by Fasya from GZM Blitzkrieg mod team.
Armor fitted over the standard S44 uniform
Camo uniform, no armor
Armor over camo uniform
How the real things looked
(too bad the Soviet inf model has no flamethrower variant)
Assault groups originated during the defense of Stalingrad and were used through the war, up to the battle of Berlin. They wore steel body armor (about 2-3 mm thick) which provided protection against melee weapons, small shrapnel and sometimes bullets. They were mainly deployed during urban battles where their slower movement speed (due to armor weight) mattered less than their close-range protection (especially against SMG fire and hand grenades).
Edit: changed URL for pic 4, should work now.