Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 e3a47b89d96d1648…

MALICIOUS

RTF / .DOC

44.8 KB
MD5: f9a9e02d320ae1d2d6c2990a86c01775 SHA-1: e57f3da7a482857d8815472b60ee488f165a1647 SHA-256: e3a47b89d96d1648c524e522239827897194653cb32d8b547a0cc301cf254cb2
120 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1059.001 PowerShell

The sample is an RTF document that contains embedded OLE object data and specifically triggers the Equation Editor vulnerability. The ".objupdate" directive forces the OLE object to activate, leading to code execution. This is a known method for exploiting the Equation Editor vulnerability to achieve arbitrary code execution, typically for downloading and executing a second-stage payload.

Heuristics 3

  • Split hex Equation Editor ProgID + OLE object critical RTF_EQUATION_EDITOR
    RTF embeds the Equation.3 ProgID as hex bytes near OLE object activation and splits the byte stream with whitespace or an ignorable RTF group. This is an Equation Editor OLE activation surface commonly used by CVE-2017-11882 / CVE-2018-0802 exploit documents.
  • \objupdate forces OLE activation high RTF_OBJUPDATE
    RTF contains \objupdate — forces automatic OLE object instantiation when the document is opened, bypassing user interaction. Almost exclusively seen in Equation Editor exploit documents.
  • OLE object data medium RTF_OBJDATA
    RTF contains 2 \objdata section(s) — embedded OLE objects

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off000016cf.bin
7d567f155e6e6f0202ae72ff458b156368246dfe2e1c9d33249258a6668ae8e2
rtf-objdata-decoded RTF \objdata at offset 0x16CF 1730 bytes