Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 dde00eaecb6ab7ce…

MALICIOUS

RTF / .DOC

29.4 KB
MD5: fdc868b65a5939581bb049f54b476e33 SHA-1: 7f25be990fc7371a0c5778353b11e3a1a616effd SHA-256: dde00eaecb6ab7ce66bc5c29647b152b90f1afa5ede133edeed2be0f0b7513c1
120 Risk Score

Malware Insights

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

The sample is an RTF document that leverages the Equation Editor vulnerability, as indicated by the RTF_EQUATION_EDITOR and RTF_OBJUPDATE heuristics. The presence of OLE object data (RTF_OBJDATA) further supports this. The primary attack vector appears to be exploitation of the Equation Editor to achieve code execution, likely for downloading and running a subsequent stage. No specific family could be identified.

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_off00001a82.bin
c0b2742197af3ae35d6cfcb2374d727f67287575dd5c3d09df58afe5e8dd4ea2
rtf-objdata-decoded RTF \objdata at offset 0x1A82 2224 bytes