Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 8bf660fca11a88aa…

MALICIOUS

RTF / .DOC

28.8 KB
MD5: b028a4e12d067acd5fc39e6a053d6148 SHA-1: a5966f6c978be564d16dff5f8a23f18dae342448 SHA-256: 8bf660fca11a88aad4524d5b17b9636ba75dfd81a19b1d950019d393c192eab7
160 Risk Score

Malware Insights

MITRE ATT&CK
T1204.002 Malicious File T1559.002 Component Object Model

The RTF document contains embedded OLE objects, specifically targeting the Equation Editor component. The presence of RTF_EQUATION_EDITOR and RTF_OBJAUTLINK heuristics indicates an attempt to exploit a known vulnerability in the Equation Editor to achieve arbitrary code execution. The ".objupdate" directive further suggests that the embedded object is designed to be activated automatically upon opening the document.

Heuristics 4

  • 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.
  • Automatically linked OLE object high RTF_OBJAUTLINK
    RTF contains \objautlink — an automatically linked OLE object surface that can be updated or activated when Word opens the document.
  • \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_off00001ab1.bin
589e566d46c8d9ac9e0f317d7f2d130cffca1bfc23baa55621eee5dc2eaf9ab0
rtf-objdata-decoded RTF \objdata at offset 0x1AB1 1378 bytes