The Cybersecurity and Infrastructure Security Agency (CISA) today asked all U.S. federal executive branch departments and agencies to mitigate the critical SIGRed Windows DNS Server wormable remote code execution (RCE) vulnerability within 24 hours.
Microsoft issued a security update to address this critical Windows vulnerability tracked as CVE-2020-1350 on July 14, together with a registry-based workaround that does not require a server restart.
The security flaw has existed in Microsoft’s code for over 17 years, it impacts all Windows Server versions 2003 through 2019, and it has received a maximum CVSS severity rating of 10 out of 10.
Mitigate on all Windows Server systems within 24 hours
“CISA has determined that this vulnerability poses unacceptable significant risk to the federal Civilian Executive Branch and requires an immediate and emergency action,” the agency said in an emergency directive issued today.
“This determination is based on the likelihood of the vulnerability being exploited, the widespread use of the affected software across the Federal enterprise, the high potential for a compromise of agency information systems, and the grave impact of a successful compromise.”
CISA’s emergency directive requires agencies to update all endpoints running Windows Server operating systems within 24 hours (by 2:00 pm EST, Friday, July 17, 2020).
Update all endpoints running Windows Server operating systems.
a. By 2:00 pm EDT, Friday, July 17, 2020, ensure the July 2020 Security Update or registry modification workaround is applied to all Windows Servers running the DNS role.
b. By 2:00 pm EDT, Friday, July 24, 2020, ensure the July 2020 Security Update is applied to all Windows Servers and, if necessary and applicable, the registry change workaround is removed.
c. By 2:00 pm EDT, Friday, July 24, 2020, ensure technical and/or management controls are in place to ensure newly provisioned or previously disconnected servers are updated before connecting to agency networks.
The agency says that these requirements only apply to “Windows Servers in any information system, including information systems used or operated by another entity on behalf of an agency, that collects, processes, stores, transmits, disseminates, or otherwise maintains agency information.”
Not all agencies are required to comply
CISA also recommends removing all Windows Server systems that can’t be updated within 7 business from the agencies’ networks.
Federal agencies are required to comply with emergency directives issued by CISA to protect systems from security threats according to the U.S. Code, however, they do not apply to the Department of Defense or the Intelligence Community (the Central Intelligence Agency and the Office of the Director of National Intelligence.
Even though the directive only applies to Executive Branch departments and agencies, CISA also urges state and local governments, the private sector, and others to urgently patch this critical vulnerability.
Although this Directive only applies to federal agencies, we strongly recommend that all our partners in private industry and government take the same actions. Remember, we offer Cyber Hygeiene and other free services: https://t.co/FqFmIpJfgN #InfoSec
— Cybersecurity and Infrastructure Security Agency (@CISAgov) July 16, 2020
The U.S. National Security Agency (NSA) also issued an advisory today urging to apply the CVE-2020-1350 patch immediately to all Windows Servers.
“Internet-facing Windows Servers with DNS server roles will have significant vulnerability risk and should patch or apply the workaround mitigation as soon as possible,” the NSA said.