Microsoft is persuading customers to download software patches after state-sponsored hackers from China broke into a few customers’ copies of its software for email, contacts and calendar via various previously unfound flaws.
Microsoft said the attackers had used the vulnerabilities to hack into Microsoft Exchange Server, which let them get into the accounts and put in malware that would “facilitate long-term access to victim environments.”
The blog added that Microsoft had come out with patches to fix the flaws, saying that, “Microsoft has detected multiple 0-day exploits being used to attack on-premises versions of Microsoft Exchange Server in limited and targeted attacks.”
Zero-day vulnerabilities are very valuable for hackers as they do not have any defences against them until they have been found and patches have been developed. So, security researchers and hackers, bath are constantly looking for undiscovered vulnerabilities for various reasons.
“We are sharing this information with our customers and the security community to emphasize the critical nature of these vulnerabilities and the importance of patching all affected systems immediately,” the company said. It also said that although the on-premise systems had been affected, the online version of Exchange had not been.
The hackers behind this are “a group assessed to be state-sponsored and operating out of China,” according to the blog. They typically target “entities in the United States across a number of industry sectors, including infectious disease researchers, law firms, higher education institutions, defence contractors, policy think tanks, and NGOs,” the blog said.