Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 4524b17b0596fc6b…

MALICIOUS

RTF / .DOC

16.2 KB
MD5: fc04c092989b2b86863c18979b04e1c3 SHA-1: 3619e13c299ca621e348a9a57f03f6500d23429a SHA-256: 4524b17b0596fc6bb80fed231fe53ca854f2319878c0c1e2805b3b5710bb64e8
160 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution

The sample is an RTF document containing embedded OLE objects, specifically targeting the Equation Editor vulnerability. The heuristics RTF_EQUATION_EDITOR, RTF_OBJAUTLINK, and RTF_OBJUPDATE strongly indicate exploitation of this component. The embedded OLE object data, when decoded, likely contains the exploit code. The primary attack vector is the exploitation of the Equation Editor to achieve arbitrary code execution.

Heuristics 4

  • 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.
  • Automatically linked OLE object high RTF_OBJAUTLINK
    RTF contains \objautlink — an automatically linked OLE object surface that can be updated or activated when Word opens the document.
  • \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_off00000e3f.bin
ba85c77b289b39ac6f597e4b8562f3006fbd05da27887df7c501e6822ed7fe0e
rtf-objdata-decoded RTF \objdata at offset 0xE3F 1571 bytes