Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 adf8ee9b13fdad76…

MALICIOUS

RTF / .DOC

3.9 KB
MD5: f01a9fb42fbcb8dd47594d9ed587653c SHA-1: 6153ac800fb8ca36ce306c315c68c3c4314764bc SHA-256: adf8ee9b13fdad76805ff5d94df7bab6cc4847aedb8da87fe57f70756daf9af3
160 Risk Score

Malware Insights

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

The RTF document contains multiple indicators of exploitation targeting Microsoft Equation Editor, including OLE object data and automatic linking. The critical RTF_EQUATION_EDITOR heuristic strongly suggests a vulnerability exploit. The embedded OLE object data is likely the payload delivery mechanism. The document body contains only a number, providing no contextual lure.

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_off000000a9.bin
85cb79a1fad3be348e6177bf8b4fe2f2f80ea7740ae3239bf913b93daa55d089
rtf-objdata-decoded RTF \objdata at offset 0xA9 1758 bytes