Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 31e0ea87983451b4…

MALICIOUS

RTF / .DOC

7.5 KB
MD5: 2c15d6b5dacee38f2b9d5bb1236f0bc3 SHA-1: 9a217860103db9c5b8e0eb4d9c5e0d5667b8f390 SHA-256: 31e0ea87983451b4c759b630005e2cdfe620c49eebef6bd0d8552268abd322c7
160 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious File

The RTF document contains multiple indicators of exploiting the Equation Editor vulnerability, including OLE object data and automatic linking. The critical RTF_EQUATION_EDITOR heuristic strongly suggests this is the primary attack vector. The presence of OLE objects and the objupdate flag indicate that the embedded object is designed to be activated, likely leading to the execution of a secondary payload. No specific family could be identified, and no further IOCs were extracted.

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 1 \objdata section(s) — embedded OLE objects

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off00000912.bin
22b89a584b3a5b61d7dd7f83dbf132cbf1b12b88fa535ba63da69c57d3ab0289
rtf-objdata-decoded RTF \objdata at offset 0x912 1393 bytes