Stack-based buffer overflow in Symantec Decomposer, as used in certain Symantec antivirus products including Symantec Scan Engine 5.1.2 and other versions before 5.1.6.31, allows remote attackers to execute arbitrary code or cause a denial of service (application crash) via a malformed RAR file to the Internet Content Adaptation Protocol (ICAP) port (1344/tcp).