Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 424dfced46a59028…

MALICIOUS

RTF / .DOC

48.8 KB First seen: 2023-01-13
MD5: 1f47a7aaa577bb663d083d446597136b SHA-1: 823af8efd3f2cabf40e96b80d00b99a77c8636c5 SHA-256: 424dfced46a590287ed2a616fce6a042127ccce6df42e6d50f0cdb0df010d090
140 Risk Score

Malware Insights

MITRE ATT&CK
T1204 Malicious Link T1204.002 Malicious Link: Malicious File T1059 Command and Scripting Interpreter T1059.005 Command and Scripting Interpreter: Visual Basic

The RTF document contains an embedded OLE object with a specific Equation Editor ProgID, and the ".objupdate" directive forces OLE activation. The document body includes a lure instructing the user to 'Enable editing' to view the content, which is a common technique for malware droppers to bypass security settings. This strongly suggests an exploit targeting the Equation Editor vulnerability to execute a payload.

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.
  • \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
  • 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_off00005817.bin
5a2af60bc0e2ab392422df93e1854df0fca7e353111716a8a9ab1ae5ea246335
rtf-objdata-decoded RTF \objdata at offset 0x5817 1844 bytes