Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 501575c02253dc7e…

MALICIOUS

RTF / .DOC

38.4 KB First seen: 2023-07-24
MD5: f32ac2000246e47a51d3345c7ca60f1d SHA-1: c02115a1c325eec4b400ee7ccdc78592b5f5406d SHA-256: 501575c02253dc7e900cd236d00678dc1d51031fb5943107918b84e55de6a923
140 Risk Score

Malware Insights

MITRE ATT&CK
T1204 Malicious Link T1059 Command and Scripting Interpreter

The sample is an RTF document containing an embedded OLE object with a split Equation Editor ProgID, indicating an attempt to exploit CVE-2017-11882. The ".objupdate" directive further suggests that the OLE object is designed to be activated automatically. The document also contains a lure instructing the user to 'Enable editing', a common tactic for macro-based malware delivery. While no specific payload or second-stage URL was directly extracted, the exploit and lure strongly suggest a malicious dropper.

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_off000044aa.bin
c513db11a27d1a76c58f77860796b565fec28d1eb6bef41a6dec02c7fd58b347
rtf-objdata-decoded RTF \objdata at offset 0x44AA 1585 bytes