Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 559699ef7f04f7b1…

MALICIOUS

RTF / .DOC

18.9 KB First seen: 2023-06-06
MD5: ce9c82e5d11b11812e5419826afe7b27 SHA-1: d762070b78ce86dafa563d82bad1eb57ca837fbf SHA-256: 559699ef7f04f7b186ad17c34f1fd54e856f6f2add3d1ed2a3a3be49afef8d02
120 Risk Score

Malware Insights

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

The file is an RTF document that contains an embedded OLE object, specifically targeting the Equation Editor vulnerability. The presence of `RTF_EQUATION_EDITOR` and `RTF_OBJUPDATE` heuristics indicates that the file is designed to exploit this known vulnerability. The `RTF_OBJDATA` heuristic further confirms the embedding of OLE object data, which is the mechanism for delivering the exploit. The primary goal is likely to achieve code execution for downloading and running a secondary malicious payload.

Heuristics 3

  • 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.
  • \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_off000010be.bin
f0170d323d7d6bba0e0cb0e6aa6280446dabf4ad284491eedc426d51b7c7f880
rtf-objdata-decoded RTF \objdata at offset 0x10BE 1892 bytes