This indicates an attack attempt against a remote Code Execution vulnerability in Oracle Java Runtime Environment.
The vulnerability is caused by an error when the software handles specially crafted jar file. It allows a remote attacker to write and execute files on a victim's computer.
Sun JRE 1.7.0_4
Sun JRE 1.7.0_2
Sun JRE 1.7
Sun JDK 1.7.0_4
Sun JDK 1.7.0_2
Sun JDK 1.7
System Compromise: Remote attackers can gain control of vulnerable systems.
Apply the most recent upgrade or patch from the vendor.