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MSCI Alert

2021-005A-Worldwide-DarkSide Ransomware Joint Cybersecurity Advisory


Re-transmittal of Cybersecurity and Infrastructure Security Agency (CISA)/Federal Bureau of
Investigation (FBI) Alert AA21-131A dated May 11, 2021: “The Cybersecurity and
Infrastructure Security Agency (CISA) and the Federal Bureau of Investigation (FBI) are aware
of a ransomware attack affecting a critical infrastructure (CI) entity—a pipeline company—in the
United States. CISA and FBI urge CI asset owners and operators to adopt a heightened state of
awareness and implement the recommendations listed in the Mitigations section of this Joint
Cybersecurity Advisory, including implementing robust network segmentation between IT and
OT networks; regularly testing manual controls; and ensuring that backups are implemented,
regularly tested, and isolated from network connections.” The full text of this Joint Cybersecurity
Advisory is available at

For any questions about this Alert, please utilize the contact info within the CISA Alert at the
above URL.