Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 6a927471061f1aab…

MALICIOUS

RTF / .DOC

4.4 KB
MD5: 4d3c72f041892712bd88865c40ae41ec SHA-1: f33b5a79d6e1fafa451676efff54064d35857316 SHA-256: 6a927471061f1aab7dcc61f9743f845438f09c3dfd5b2bcf458417bc2d15b864
120 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1566.001 Spearphishing Attachment

The RTF document contains embedded OLE objects and specifically triggers the Equation Editor vulnerability. The ".objupdate" directive forces the activation of the embedded OLE object, leading to the exploitation of the Equation Editor to execute arbitrary code. This is a common technique for delivering malicious payloads.

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_off000000c9.bin
62881deaaf7db8175cf2930736a4db75e6b2032c96b4a2921a838007c11490b7
rtf-objdata-decoded RTF \objdata at offset 0xC9 1960 bytes