Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 2cdd65a3b889cda9…

MALICIOUS

RTF / .DOC

4.1 KB
MD5: 5ff50bac624822c216da96577b2a0c0a SHA-1: fa4df3d9d18e856a4156a08aa8fc3e6393011d99 SHA-256: 2cdd65a3b889cda978747bc8787b55d6a4f5df81e6aa14cf49102262cfa77380
160 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious File T1059.003 Windows Command Shell

The file is an RTF document that leverages the Equation Editor vulnerability (CVE-2017-11882). The presence of OLE object data and specific RTF heuristics strongly indicate an attempt to exploit this known vulnerability. The exploit likely leads to the execution of a secondary payload, although no specific payload details or network indicators were extracted from this sample.

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_off000000bf.bin
b89f9e024d24fb54958391127299025922b8a49660f96804cfaf7c2e7b854f1e
rtf-objdata-decoded RTF \objdata at offset 0xBF 1911 bytes