Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 5a035ffb0a0f4eaa…

MALICIOUS

RTF / .DOC

20.1 KB
MD5: 3e5e7b54b4c3811dcf4801b34e72f917 SHA-1: dba151a687672d09af3dac0493e9b85d13a85eab SHA-256: 5a035ffb0a0f4eaade9524a37c4f55468e8cf4e8c429e404bb33fcdc2da27f17
120 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 User Execution: Malicious File T1203 Exploitation for Client Execution

The file is an RTF document that contains embedded OLE object data, specifically targeting the Equation Editor vulnerability. The presence of `RTF_EQUATION_EDITOR` and `RTF_OBJUPDATE` heuristics indicates that the document is designed to exploit this vulnerability upon opening, leading to arbitrary code execution. The `RTF_OBJDATA` heuristic further confirms the embedding of OLE objects, which is a common delivery mechanism for exploits. The embedded artifact `objdata_00_off000017f6.bin` is likely the exploit 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 2 \objdata section(s) — embedded OLE objects

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off000017f6.bin
61aff99a6d1553e2265e85bd710e6d156dfbf8ba965b4a59d41ff603469881ab
rtf-objdata-decoded RTF \objdata at offset 0x17F6 1882 bytes