At least 10 hacking groups using Microsoft software flaw - researchers

FILE PHOTO: Silhouettes of laptop and mobile device users are seen next to a screen projection of Microsoft logo in this picture illustration taken March 28, 2018. REUTERS/Dado Ruvic/Illustration/File Photo

WASHINGTON (Reuters) - At least 10 different hacking groups are using recently discovered flaws in Microsoft Corp's mail server software to break in to targets around the world, cybersecurity company ESET said in a blog post on Wednesday.

The breadth of the exploitation adds to the urgency of the warnings being issued by authorities in the United States and Europe about the weaknesses found in Microsoft's Exchange software.