The drv2.dll (aka RV20 decompression) module in RealNetworks RealPlayer 11.0 through 11.1, RealPlayer SP 1.0 through 1.1.5, RealPlayer Enterprise 2.1.2 and 2.1.3, Linux RealPlayer 11.0.2.1744, and possibly HelixPlayer 1.0.6 and other versions, allows remote attackers to execute arbitrary code or cause a denial of service (heap memory corruption) via a crafted value of an unspecified length field in an RV20 video stream.