CISA Alert AA22-277A – Impacket and exfiltration tool used to steal sensitive information from defense industrial base organization.

This is a CISA Cybersecurity Alert. ID number Alpha Alpha Two Two tack Two Seven Seven Alpha.

Original release date: October fourth, twenty twenty two.

From November 2021 through January 2022, the CISA responded to APT activity against a Defense Industrial Base organization’s enterprise network. During incident response activities, CISA discovered that multiple APT groups compromised the organization’s network, and some APT actors had long-term access to the environment. APT actors used an open-source toolkit called Impacket to gain their foothold within the environment and further compromise the network, and also used a custom data exfiltration tool, CovalentStealer, to steal the victim’s sensitive data.

Impacket uses Windows Management Instrumentation and Server Message Block protocol to create a semi-interactive shell with the target device. Through the Command Shell, an Impacket user with credentials can run commands on the remote device using the Windows management protocols required to support an enterprise network.

CovalentStealer is designed to identify file shares on a system, categorize the files, and upload the files to a remote server. CovalentStealer includes two configurations that target the victim's documents using predetermined file paths and user credentials. CovalentStealer stores the collected files on a Microsoft OneDrive cloud folder.

The alert documentation listed in the show notes provides the APT actors tactics, techniques, and procedures and IOCs for the threat activity. The alert documentation also includes detection and mitigation actions to help organizations prevent this APT activity. CISA, FBI, and NSA recommend Defense Industrial Base organizations implement the mitigations listed in this alert to ensure they are managing and reducing the impact of cyber threats to their networks.

CISA, FBI, and NSA acknowledge Mandiant for its contributions to this alert.

To report incidents and anomalous activity or to request incident response resources or technical assistance, contact CISA at report@cisa.gov, or call (888) 282-0870, or report incidents to your local FBI field office.

This report was written by CISA, the United States Cybersecurity and Infrastructure Security Agency, and edited and adapted for audio by the CyberWire as a public service. Please visit www dot cisa dot gov to read the full report which may include additional details, links, and illustrations. A link to this report can be found in the show notes.