Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 71d8f6bfc8cb5696…

MALICIOUS

RTF / .DOC

44.2 KB First seen: 2023-02-16
MD5: 971e49dc5ba2002e1c5804a6cdb5ece7 SHA-1: 47049091096af2fe5243f7a839f661600bb8c811 SHA-256: 71d8f6bfc8cb569664e7efe59132c582fd7472d3ab47a9c4346c182fadd84b55
140 Risk Score

Malware Insights

MITRE ATT&CK
T1204 User Execution T1059.005 Visual Basic

The sample is an RTF document containing an embedded OLE object, specifically targeting the Equation Editor vulnerability. The document body presents a lure related to a marketing assignment, instructing the user to 'Enable editing' to view the content. This combination strongly suggests an attempt to exploit the Equation Editor vulnerability via OLE object activation to execute a malicious 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_off00004b13.bin
4cad146908fde1625a0914e944b2f798c6e07d40fc79fcc3569c2e3854afb20f
rtf-objdata-decoded RTF \objdata at offset 0x4B13 2121 bytes