Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 b873313c6856102f…

MALICIOUS

RTF / .DOC

58.7 KB
MD5: 083083666b8d28b06db9bc17ea30e524 SHA-1: 9299438a48d944f22f729a95411a57bee9e1a23c SHA-256: b873313c6856102fb8f7cdb84be0220f514610fc101f0dfc99282e5b162d6669
160 Risk Score

Malware Insights

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

The RTF document contains embedded OLE objects, specifically triggering critical heuristics related to Equation Editor vulnerabilities. The presence of \objupdate and \objautolink directives indicates that the embedded object is designed to be automatically activated upon opening, leading to the exploitation of the Equation Editor component. This is a common delivery mechanism for exploiting known vulnerabilities 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_off000010ff.bin
8c40ce214da6b26b78da130c4d0469ec659bb3a3e2ce8f94c0cb90ddfca5f854
rtf-objdata-decoded RTF \objdata at offset 0x10FF 2044 bytes