This indicates an attack attempt against a Stack Buffer Overflow vulnerability in Samsung SmartViewer.
The vulnerability, which is located in an ActiveX control, can be exploited through a vulnerable method. An attacker can exploit this by tricking an unsuspecting user into visiting a malicious webpage and execute arbitrary code within the context of the users' browser.
Samsung SmartViewer prior to 4.4.3
System Compromise: Remote attackers can execute arbitrary code within the context of the target user's browser
Apply the most recent upgrade or patch from the vendor.