Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 ec65a730a077bb53…

MALICIOUS

RTF / .DOC

27.8 KB
MD5: 38f813f2ba419013daa31f38954abad7 SHA-1: 1b87a3ab4f79c98eb469e6e00becd68e2d16a272 SHA-256: ec65a730a077bb53eb97495b33df1926cbb349211b2daa4fe03f46805f9197cd
160 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious File T1059.003 Windows Command Shell

The RTF document contains OLE object data and an automatically linked OLE object, specifically targeting the Equation Editor. The presence of RTF_EQUATION_EDITOR and RTF_OBJUPDATE heuristics indicates that the document is designed to exploit a vulnerability in the Equation Editor to achieve arbitrary code execution upon opening. This is a common delivery mechanism for malware.

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_off0000163e.bin
1f705685381096178158b92b1002ce4f99516698cfa5392fbec34764d370d159
rtf-objdata-decoded RTF \objdata at offset 0x163E 1930 bytes