Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 2a3f9ee6932dd327…

MALICIOUS

RTF / .DOC

100.9 KB
MD5: e8cba98a1072120f172eadef52f1adbc SHA-1: fafcb361df4bdcf4e01258fc5a377d6a09c9d31d SHA-256: 2a3f9ee6932dd327041b7a1a4eeb592575aecec28f45b94612dd31f098953dd1
160 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1559.001 Component Object Model Hijacking

The RTF document contains embedded OLE objects, specifically triggering heuristics related to Equation Editor exploitation. The presence of ".objdata" and ".objupdate" directives strongly suggests an attempt to leverage the Equation Editor vulnerability (CVE-2017-11882) for arbitrary code execution. This is a common delivery mechanism for various malware families.

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_off000002ec.bin
39181a5fd87bbc924b0bec8e42820eae47adb0656404aaa15b6dcb557b5a271a
rtf-objdata-decoded RTF \objdata at offset 0x2EC 1786 bytes