Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 64b1d890d99d612a…

MALICIOUS

RTF / .DOC

15.9 KB First seen: 2023-02-22
MD5: 948ff536acc99d28c981ef991eaad1bf SHA-1: c411e19abe1b1b5117175653b852a76c54093756 SHA-256: 64b1d890d99d612a158645aa2a5038800bc506ec3467ecf9294b3e083be39936
120 Risk Score

Malware Insights

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

The sample is an RTF document that triggers critical and high severity heuristics related to Equation Editor exploitation and OLE object activation. This indicates the file is designed to exploit a known vulnerability in Microsoft Equation Editor to achieve code execution. The embedded OLE object data further supports this attack vector. The exact payload or subsequent actions are not discernible from the provided evidence, but the primary goal is exploitation.

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_off0000194e.bin
9c9a4ce3cdc9cc0b34ba07e0192032fa087b89fc60c5616c351ae3dadf048cf0
rtf-objdata-decoded RTF \objdata at offset 0x194E 2050 bytes