The Java Virtual Machine (JVM) in Sun Java Runtime Environment (JRE) in SDK and JRE 1.3.x through 1.3.1_20 and 1.4.x through 1.4.2_15, and JDK and JRE 5.x through 5.0 Update 12 and 6.x through 6 Update 2, allows remote attackers to execute arbitrary programs, or read or modify arbitrary files, via applets that grant privileges to themselves.