Malicious RTF — malware analysis report

Static analysis result for SHA-256 7f7c0a8e3904766b…

MALICIOUS

RTF

92.7 KB First seen: 2024-07-30
MD5: cf3ae921fc075c967cac5a5e384849bc SHA-1: aa1ef73f7b20a698c7d5bdffaf0d49daa3cc6628 SHA-256: 7f7c0a8e3904766b34045e77f1eb2ae131dbcba2b9db93a882245cae5bb8efd9
120 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1059.001 PowerShell

The RTF file contains an embedded OLE object that leverages a known vulnerability in the Equation Editor component. The presence of `RTF_EQUATION_EDITOR` and `RTF_OBJUPDATE` heuristics strongly indicates exploitation of this vulnerability. The embedded OLE object, decoded as `objdata_00_off00001fa9.bin`, is the likely mechanism for delivering a secondary payload, although its specific contents could not be determined from the provided evidence.

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_off00001fa9.bin
0afcb9cc588b438ed96c05684316fdc1ecbef14701c2e9693a83c2bf748b4ed2
rtf-objdata-decoded RTF \objdata at offset 0x1FA9 1831 bytes