Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 8179a1222c54acb8…

MALICIOUS

RTF / .DOC

30.5 KB First seen: 2022-12-06
MD5: ff8835cb52f91a82d993ac250b7ddaa8 SHA-1: 9577e4efd05c374b76a09c00996f9a889e1be9b1 SHA-256: 8179a1222c54acb84d7d36cafd86da69a3901e603dc92aa8fa939ead66a5c633
140 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious File

The RTF document contains an embedded OLE object with a split Equation Editor ProgID, indicating an attempt to exploit a known vulnerability. The \objupdate directive forces OLE activation, and the document body includes a lure to 'Enable editing', suggesting a malicious dropper designed to execute a payload via the Equation Editor vulnerability.

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_off0000548a.bin
1715551405cbf8679abf36931cc001e360c3321e3d60155b2a314671a255622f
rtf-objdata-decoded RTF \objdata at offset 0x548A 1733 bytes