Java, Adobe Reader and Flash accounted for two-thirds of the vulnerabilities exploited by malware on Microsoft’s Windows operating system since 2000, a new study by AV-Test Institute revealed.

Security researchers said such vulnerabilities would allow Trojans and other malware types to attack PC systems.

According to the analysis, one of the exploits for Adobe Reader achieved the top spot with nearly 37,000 different variants recorded, followed by the initial Java version with more than 31,000 different exploits, while 20,000 specially produced vulnerabilities were recorded in Adobe Flash.

Java topped the list with over 82,000 attackers, which make it the top vulnerability for exploit attacks.

Researchers advised users to keep their applications software updated to boost the security of their systems.

Within the past five to ten years, both Adobe and Microsoft have boosted their software development processes by bringing down the overall vulnerabilities, the report said.

It added that the latest versions of Windows as well as both Microsoft and Adobe applications, are more highly secured than in 2000, or even 2008.