Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 368a2e52bc0a5d89…

MALICIOUS

RTF / .DOC

131.7 KB First seen: 2023-10-25
MD5: 37c6f075b0d8e87dee4e5aad8d883d9d SHA-1: 1a53854cdbba81d085367c4f65283d487917a687 SHA-256: 368a2e52bc0a5d89a0de8cf1562c56f9a200ce834d5c4caae83afcb5ed7d6d98
140 Risk Score

Malware Insights

MITRE ATT&CK
T1204 Malicious Link T1204.002 Malicious Link: Malicious File

The sample is an RTF document containing an embedded OLE object that leverages the Equation Editor vulnerability. The document body contains a lure instructing the user to 'click Enable editing from the yellow bar above', which is a common technique to bypass Office macro security settings and trigger the exploit. The presence of RTF_OBJDATA, RTF_EQUATION_EDITOR, and RTF_OBJUPDATE heuristics confirms the exploitation attempt.

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_off000032be.bin
18c2a4ee43797e4537a47ad8421028ce36577219bfd7178cb4cec89793921490
rtf-objdata-decoded RTF \objdata at offset 0x32BE 1641 bytes