Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 efeaddcf237dfbe2…

MALICIOUS

RTF / .DOC

4.1 KB First seen: 2022-06-21
MD5: 365b5e8dc280f55842209d121f8c6266 SHA-1: 0a2564cbb59240a7d8c035e2e7d3ac3a38e1a172 SHA-256: efeaddcf237dfbe27e0bea158fcdfb05a56fe0fe78381d2f8e0501a45fdc1689
200 Risk Score

Malware Insights

MITRE ATT&CK
T1204 Malicious Link T1559 Component Object Model Hijacking T1059.001 PowerShell T1204.002 Malicious File

The RTF document contains embedded OLE object data and specifically targets the Equation Editor vulnerability (CVE-2017-11882). The presence of `RTF_EQUATION_EDITOR` and `CVE_2017_11882_ACTIVATION_RELATED` heuristics strongly indicates exploitation of this known vulnerability. The `RTF_OBJUPDATE` heuristic suggests that the embedded object is automatically activated upon opening the document, leading to arbitrary code execution. The decoded object data contains the ProgID `EQUaTiON.3`, which is characteristic of this exploit.

Heuristics 5

  • Equation Editor activation — CVE-2017-11882 related high CVE related CVE_2017_11882_ACTIVATION_RELATED
    RTF decodes to an Equation.3 ProgID and requests OLE activation with \objemb plus \objupdate. This reaches the legacy Equation Editor attack surface used by CVE-2017-11882/CVE-2018-0802 documents, but the malformed MTEF/native payload needed for stronger attribution was not recovered.
  • 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_off00000084.bin
8f770e3b8c5f4b5c2df2da0f64ff80aee707cf3df5207e13a387777056df1d44		 rtf-objdata-decoded RTF \objdata at offset 0x84 1661 bytes

Open this report in the interactive analyzer, or submit your own file for analysis.