Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 c229865edb6f6578…

MALICIOUS

RTF / .DOC

75.8 KB First seen: 2023-09-19
MD5: b86d50234603bbdd5a29aae42a858757 SHA-1: 557f1df7179b83ecb1afe0931432fe7a5d405bd7 SHA-256: c229865edb6f65789b254473557a849fc7930a7d24e7ecb4a96b9e7f7695267f
140 Risk Score

Malware Insights

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

The file is an RTF document that contains an embedded OLE object, specifically targeting the Equation Editor vulnerability. The document body includes a lure instructing the user to 'click Enable editing', which is a common tactic to bypass security measures and trigger the exploit. The presence of RTF_OBJDATA and RTF_OBJUPDATE heuristics further 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_off00003364.bin
46d33dd558272aaf9566b6d8586ff63cbf28a2fff9fb64fb2b4c66e0d340857e
rtf-objdata-decoded RTF \objdata at offset 0x3364 1756 bytes