Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 9e979a696a42b87f…

MALICIOUS

RTF / .DOC

20.2 KB
MD5: a174380b6e9f839091c8798bcc101a70 SHA-1: db317383e265eeb6a77915bae740526d290e06b5 SHA-256: 9e979a696a42b87f2636f283b777eea10f94e31b2f536a6f4f91468f36fcc9e6
120 Risk Score

Malware Insights

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

The sample is an RTF document that leverages the Equation Editor vulnerability (CVE-2017-11882) via embedded OLE objects. The critical heuristic 'RTF_EQUATION_EDITOR' and the high heuristic 'RTF_OBJUPDATE' strongly indicate exploitation of this known vulnerability. The presence of OLE object data suggests the document is designed to trigger code execution upon opening, likely to download and execute a secondary payload.

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_off00001aa7.bin
3551eec9be2d9afbd42e793d7e58e7b392a2397c8defce8d86f9520fe43a7cdf
rtf-objdata-decoded RTF \objdata at offset 0x1AA7 1794 bytes