Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 31b1b60f816baad9…

MALICIOUS

RTF / .DOC

19.3 KB
MD5: 078964225de88f9310c868c1cc0a2d81 SHA-1: b4198e1c93cd1301b45f96f81dad056c5669ebfe SHA-256: 31b1b60f816baad94a5bfb8d21ece987c2817cebdd3447cc95e4a7869e08eed3
160 Risk Score

Malware Insights

MITRE ATT&CK
T1204 Malicious Link T1059 Command and Scripting Interpreter

The file is an RTF document that contains embedded OLE objects, specifically targeting the Equation Editor vulnerability. The presence of `RTF_EQUATION_EDITOR`, `RTF_OBJAUTLINK`, `RTF_OBJUPDATE`, and `RTF_OBJDATA` heuristics strongly indicates that this document is designed to exploit a known vulnerability in Microsoft Equation Editor. This exploit likely leads to the download and execution of a secondary malicious payload, a common technique for initial access.

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_off00001042.bin
1de7ccdb9e1e6792c0a5182bc934dac325bbfcd03168735297241ceedd86bc8f
rtf-objdata-decoded RTF \objdata at offset 0x1042 1451 bytes