Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 da6a6a53406e85dd…

MALICIOUS

RTF / .DOC

22.2 KB
MD5: 8b00f8de00570d932f16b7f1fe4cd61a SHA-1: 521c6f5efd116c2de7e68a7df7208ca88f7c6349 SHA-256: da6a6a53406e85dd8b388cfb5d63c723ec59c6c70226cd821e8d36a4dcb63e66
160 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious File

The RTF document contains OLE object data and an automatically linked OLE object, specifically targeting the Equation Editor. The presence of `RTF_EQUATION_EDITOR` and `RTF_OBJUPDATE` heuristics indicates a likely exploit leveraging the Equation Editor vulnerability to execute arbitrary code upon opening the document. This is a common delivery mechanism for initial compromise.

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_off00001ca5.bin
21b8ada33dee0baf64f86412b186b07de127b4456786cc7614c80260c0253e14
rtf-objdata-decoded RTF \objdata at offset 0x1CA5 1493 bytes