Feds Discover Additional Microsoft Exchange Vulnerabilities The U.S. National Security Agency discovered and notified Microsoft of two Exchange Server vulnerabilities that could allow hackers to persistently access and control enterprise networks. By Michael Novinson April 13, 2021, 06:07 PM EDT The U.S. National Security Agency discovered and notified Microsoft of two Exchange Server vulnerabilities that could allow hackers to persistently access and control enterprise networks. The latest flaws impact on-premises Microsoft Exchange Servers 2013, 2016, and 2019, and could be exploited by adversaries to gain access and maintain persistence on the target host, according to the Cybersecurity and Infrastructure Security Agency. These flaws are likely to be weaponized, and CISA said there’s high potential they could compromise the integrity and confidentiality of agency information.