The Department of Homeland Security’s Cybersecurity and Infrastructure Security Agency (CISA) has issued a supplemental directive requiring all federal agencies to identify vulnerable Microsoft Exchange servers in their environments within five days.
Providing additional direction on the implementation of CISA Emergency Directive 21-02, which on March 3 requested federal agencies to take the necessary steps to disconnect and update Exchange servers, the new directive demands agencies to accelerate the mitigation process.
The new requirements are meant to complement the initial directive and apply to all operational Exchange servers that are either hosted by or on behalf of federal agencies and which had been connected to the Internet “at any time since January 1, 2021.”
CISA says that federal agencies did respond to the Emergency Directive and triaged and updated Exchange servers hosted in the federal enterprise, but also notes that the new directions are meant to help identify possibly undetected compromise.
“Since the original issuance of ED 21-02, Microsoft has developed new tools and techniques to aid organizations in investigating whether their Microsoft Exchange servers have been compromised. CISA also identified Microsoft Exchange servers still in operation and hosted by (or on behalf of) federal agencies that require additional hardening,” CISA said in an advisory.
Per the new directive, federal agencies are required to download and scan their environments with the latest version of Microsoft Safety Scanner (MSERT) within the next five days (by 12:00 pm Eastern Daylight Time on Monday, April 5, 2021), and report to CISA the results of the scans.
