Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 1687b404e85c3948…

MALICIOUS

RTF / .DOC

41.6 KB First seen: 2023-02-20
MD5: 6445e4f1ba6188d6d765f9894fba27f7 SHA-1: 8054de0208de6c5776575eb39946375e9f7bc0d8 SHA-256: 1687b404e85c3948ee8926241c4304188a7a9e26c1d095f0c3cb674bd2f54d54
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 an Equation Editor ProgID, triggered by \objupdate, indicating an attempt to exploit a known vulnerability. The document body includes a lure instructing the user to 'Enable editing', a common tactic for macro-based malware droppers to bypass security settings.

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_off00005508.bin
67367498a228242755ba605fc28e77f0b0a54b3310b8fcf8a2b9582e54e4bd9e
rtf-objdata-decoded RTF \objdata at offset 0x5508 1485 bytes