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Rewterz Threat Alert – Spear Phishing Campaign Delivering HawkEye Infostealer

Severity

Medium

Analysis Summary

HawkEye, primarily an infostealer, has additional capabilities such as bypassing of AV systems and keylogging. A spear phishing campaign is detected using malicious RTF documents sent via corona-themed emails to distribute the HawkEye keylogger. While most malicious RTF documents use exploits to trigger Object Linking and Embedding (OLE) calls, in this case the documents use the \objupdate switch. A victim would need to enable macros for the infection process to begin. The embedded OLE objects, five of them in this case, appear to be macro-enabled Excel sheets. PowerShell is used to execute .NET code which downloads and executes the Hawkeye payload.

The Infection Chain

As suspected, while opening the Word document, the Excel sheet embedded within the document was loaded and immediately displayed a notification to enable the macro. The macro notification will popup multiple times even though the user closes the notification or clicks the disable button. 

The Macro Notification While the Doc. is Opening

Impact

  • Information Theft
  • Antivirus bypass
  • Credential Theft

Indicators of Compromise

Domain Name

onlinepreneur[.]id

MD5

  • 4efc395c3cd44646e2bfb9680932b811
  • 3f1de44d357ca7c278c7d333bfdd8861
  • 4e9aa334811b6a4fa6542483a34fc9c5

SHA-256

  • 0b9e5849d3ad904d0a8532a886bd3630c4eec3a6faf0cc68658f5ee4a5e803be
  • 497cd119e5245f9a7bc64b3f04ff48653e88b345e222362a1fcbbf55c3155026
  • 81934e5965f655408e2c0125cac069e00d26a0c30fced893080fb9b089e26772

Source IP

  • 45[.]64[.]97[.]178

URL

  • http[:]//onlinepreneur[.]id/manager/brain[.]exe

Remediation

  • Block the threat indicators at their respective controls. 
  • Do not enable macros for unexpected documents, following the 0 trust policy.