Heap-based buffer overflow in RealNetworks RealPlayer 10; RealPlayer 10.5 6.0.12.1040 through 6.0.12.1741; RealPlayer 11 11.0.0 through 11.0.4; RealPlayer Enterprise; Mac RealPlayer 10 10.1 and 11.0; Linux RealPlayer 10; and Helix Player 10.x allows remote attackers to execute arbitrary code via an SIPR codec field with a small length value that triggers incorrect memory allocation.