Multiple Malware Variants Distributed Through Microsoft OneNote


  • ransom-4


Spear-phishing emails with malicious Microsoft OneNote attachments were discovered delivering variants from the AsyncRAT, Formbook, Remcos, and XWorm malware families.

Multiple legitimate Microsoft Windows utilities were used to carry out the operation including cmd, BITSAdmin, PowerShell, wscript, and curl.

The adversary took advantage of the right-to-left override (RTLO or RLO) technique to convince the victim to execute files which appeared to be benign.

SkyWatchSM Alert Legend

  • small-bell


  • active-threat0-lt-green

    Active Threat

  • malware-lt-green


  • ransome-lt-green


  • warning-green


  • file-green


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    Not for Disclosure, Restricted/ Classified - Only Shared with US DHS.

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