At least 54 organizations have been breached in the attacks. Some of the attacks that targeted organizations using an exploit in Microsoft’s SharePoint server platform over the last few days have been linked to hacking groups affiliated with the Chinese government, according to a new Microsoft security blog.

The tech giants have evidence that Chinese hackers are exploiting the new bug, but warned "multiple actors" are also hacking into affected SharePoint systems.

Microsoft Corp. has determined that China-linked hacking groups are targeting deployments of its SharePoint file sharing platform. The company detailed its findings in a blog post published today.

The flaws were discovered in instances of the software installed on customer servers rather than in the cloud, the company said.