Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 a3cfe4ea161b5229…

MALICIOUS

RTF / .DOC

17.7 KB First seen: 2023-03-13
MD5: 38ef37413e135e5f4bfdc376d3b70dd8 SHA-1: adbb863b3acec0ecd85e6c24c7f1a60ad5ba5fb6 SHA-256: a3cfe4ea161b5229eaa2d6a98c838d8c1e0651f3894599e6454f83489b4e79a9
140 Risk Score

Malware Insights

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

The sample is an RTF document that leverages OLE object data and specifically targets the Equation Editor vulnerability. The document body contains a lure instructing the user to 'enable editing', which is a common tactic for macro-based malware or exploit delivery. The presence of RTF_OBJDATA and RTF_OBJUPDATE heuristics further indicates the exploitation of embedded objects.

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_off00002ffd.bin
1bdf3ecd35cd9a6483474c3c331518267d7ce23f1d79ffd1b9fca8ce5c9b8d66
rtf-objdata-decoded RTF \objdata at offset 0x2FFD 1298 bytes