Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 790387361f487e66…

MALICIOUS

RTF / .DOC

710.4 KB
MD5: 6a49589fb764ff36b90abd86a2abdbf6 SHA-1: 155291ae16040e741e6f0d5c22e90ee44af23438 SHA-256: 790387361f487e66a55f12ded347eb0acf00be6aae4571b6e110b8c44b89bb47
160 Risk Score

Malware Insights

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

The sample is an RTF document that contains an embedded OLE object, specifically triggering the CVE-2017-11882 vulnerability in Microsoft Equation Editor. This exploit allows for arbitrary code execution, which is a critical finding. The document also contains a lure to enable editing, indicating it's designed to bypass security measures and execute its payload. The specific exploit and lure suggest a malicious document intended to deliver further malware.

Heuristics 5

  • CVE-2017-11882 — Equation Editor FONT record overflow critical CVE likely CVE_2017_11882
    Equation Editor MTEF contains an overlong FONT typeface field, the vulnerable copy primitive for CVE-2017-11882. This is stronger evidence than the Equation Editor CLSID alone because it identifies the malformed record that drives code execution in EQNEDT32.EXE.
  • \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 1 \objdata section(s) — embedded OLE objects
  • Embedded OLE object medium RTF_OBJEMB
    RTF contains \objemb — embedded OLE object
  • Macro/content-enable lure medium SE_ENABLE_LURE
    Document instructs the user to enable macros or editing — a common technique used by malware droppers to bypass Office macro security settings

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off0001693f.bin
8cd4bbd96c75af8e100795654f80fd4c11c288d3510306319b885d3252427c8d
rtf-objdata-decoded RTF \objdata at offset 0x1693F 4253 bytes