Microsoft said it faced a security intrusion similar to by Facebook and Apple earlier this month.
"During our investigation, we found a small number of computers, including some in our Mac business unit, that were infected by malicious software using techniques similar to those documented by other organizations," said Matt Thomlinson, microsoft general manager of trustworthy computing security.
"We have no evidence of customer data being affected and our investigation is ongoing," Thomlinson said. "This type of cyberattack is no surprise to Microsoft and other companies that must grapple with determined and persistent adversaries."
Earlier this month malware infected computers of Facebook employees who visited a mobile application developer website.
According to Facebook, hackers exploited an unnoticed security flaw in Oracle’s Java software last month.
The company says the attackers were using a "zero-day" exploit to install the malware.
Facebook, however says there is no evidence that Facebook member data was compromised.
The social network also points out that they were not the only company to be attacked in this way.
"Facebook was not alone in this attack. It is clear that others were attacked and infiltrated recently as well," said the company. "As one of the first companies to discover this malware, we immediately took steps to start sharing details about the infiltration with the other companies and entities that were affected. We plan to continue collaborating on this incident through an informal working group and other means."
Facebook said the attack happened in spite of their systems’ running up-to-date antivirus software but no data was stolen.
The US Federal Bureau of Investigation (FBI) is working with Facebook to find out the origin of the attack.
Apple has also suffered the same fate after hackers attacked employee computers in California by exploiting a security flaw in Java. The company said, however, that no data was stolen.
Oracle has rushed to fix the security fault on five vulnerabilities in Java 7, which is said to be the version being exploited by hackers through Java’s web start applications and applets.
The update, called Java 7 Update 15, will address four client-side vulnerabilities that could be exploited.
Oracle advises that these fixes be installed as soon as possible and desktop users can install the new version from java.com or through the Java auto update.