Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 f0cd9d141194b408…

MALICIOUS

RTF / .DOC

49.4 KB First seen: 2023-06-20
MD5: 2e888f471d5be28c1f4e6e2d93b8d392 SHA-1: 6faea96df6e11baebdeecbd06868b4770e615c86 SHA-256: f0cd9d141194b4081974323fdfc622ba83bfa9552585867681386bd462b94023
140 Risk Score

Malware Insights

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

The file is an RTF document containing an embedded OLE object, specifically identified as exploiting the Equation Editor. The presence of \objupdate and SE_ENABLE_LURE heuristics indicates a strong attempt to trick the user into enabling content, which would then trigger the embedded malicious object. This is a common delivery mechanism for exploits targeting older Office vulnerabilities.

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.
  • \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
  • Macro/content-enable lure medium SE_ENABLE_LURE
    Document instructs the user to enable macros or editing — a common technique used by malware droppers to bypass Office macro security settings

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off000053ec.bin
97b191085ada1ecf343d72f052e2f72650efd675294f096c36c42b13b95a9708
rtf-objdata-decoded RTF \objdata at offset 0x53EC 2047 bytes