This indicates an attack attempt against an authorization-bypass vulnerability in Foxit PDF reader.
The vulnerability is caused by an error when the vulnerable software handles a crafted .pdf file. It allows a remote attacker to execute arbitrary programs via sending a crafted .pdf file.
Foxit Reader 2.3 before Build 3902 and 3.0 before Build 1506, including 1120 and 1301
Apply the patch available at the follolwing web site: