A regulable vibration damper, which may be utilized in a vehicle chassis, for example, may comprise a cylinder barrel that contains hydraulic fluid in sealed-off fashion, a piston that is axially movable within the cylinder barrel along a cylinder barrel axis and that divides the cylinder barrel into two working chambers, and a piston rod oriented parallel to the cylinder barrel axis and that is connected to the piston. The piston may comprise at least two fluid leadthroughs that connect the working chambers. A first valve assembly for damping piston movement in a first actuation direction may be arranged at a first fluid leadthrough, and a second valve assembly for damping piston movement in a second actuation direction may be arranged at a second fluid leadthrough. In the piston, one or more bypass ducts with throughflow cross sections of different size for the two throughflow directions may form fluidic connections between the two working chambers that bypass the vestibules.