Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 d3e9a5b41370a726…

MALICIOUS

RTF / .DOC

38.6 KB First seen: 2023-07-12
MD5: 79055da8c7237e6101b284018ab23880 SHA-1: 70951fd95d604fc35b980d02b3e47ea0f44b8255 SHA-256: d3e9a5b41370a726cbeb7c4c3a8a29b690886518ea0bf3990cf2e1e13cac20d7
140 Risk Score

Malware Insights

MITRE ATT&CK
T1204 User Execution: Malicious Link T1059.005 PowerShell T1204.002 User Execution: Malicious File

The file is an RTF document containing an embedded OLE object, specifically targeting the Equation Editor vulnerability. The document body includes a lure instructing the user to 'Enable editing', which is a common tactic to bypass macro security settings. The presence of RTF_OBJDATA and RTF_OBJUPDATE heuristics further indicates the exploitation of OLE object activation to execute code.

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_off00005030.bin
c03241f52897afdd7d7a6fe67cfec7b3c07479efc51606fbadaf3f99967d3d89
rtf-objdata-decoded RTF \objdata at offset 0x5030 1532 bytes