This indicates a possible attack against a buffer overflow vulnerability in Microsoft Reader.
This is caused by the vulnerable application's failure to adequately sanitize user supplied input. An attacker may exploit this vulnerability by sending a specially crafted .lit or .aa file. A successful exploit may allow the attacker to execute arbitrary code on a vulnerable system.
Microsoft Reader PC version 126.96.36.19943 and prior.
System Compromise: Remote attackers can gain control of vulnerable systems.
Upgrade the latest version, available from the website: