Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 879a41e8c5e17f41…

MALICIOUS

RTF / .DOC

4.3 KB
MD5: 0f8ebaec9a18622d66312f00a590df8b SHA-1: 5cdee11f0b28b459cfaacf1eba6a0fa5a33067af SHA-256: 879a41e8c5e17f41545e9f057be592d335a5dfd6dbd980a16e3a25e0972f45a3
160 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution

The RTF document contains embedded OLE objects, specifically targeting the Equation Editor vulnerability. The presence of `RTF_EQUATION_EDITOR` and `RTF_OBJUPDATE` heuristics strongly indicates exploitation of a known Equation Editor flaw to achieve arbitrary code execution. The embedded OLE object data is the primary artifact for further analysis.

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_off000000c8.bin
72e081b3634e8122b0a73a91efe93e833db3b6fcb718a820b4f1ee580d6ec0e3
rtf-objdata-decoded RTF \objdata at offset 0xC8 1885 bytes