Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 97012a8526b2c3c2…

MALICIOUS

RTF / .DOC

68.6 KB First seen: 2023-10-24
MD5: c860429617ec6fca50b2484426373265 SHA-1: 2802b095e507b381539d9ea329d495b1f3b3bbfc SHA-256: 97012a8526b2c3c230145c295857f63ff2924bb4b2e3f39aea8de7e5e6a3e0dc
140 Risk Score

Malware Insights

MITRE ATT&CK
T1204 Malicious Link T1204.002 Malicious Link: Malicious File T1059 Command and Scripting Interpreter T1059.005 Command and Scripting Interpreter: Visual Basic

The sample is an RTF document that exploits the Equation Editor vulnerability (RTF_EQUATION_EDITOR) and uses an objupdate directive to force OLE activation (RTF_OBJUPDATE). The document body contains text designed to trick the user into enabling editing and macros, a common lure for malware droppers. The presence of OLE object data further suggests the embedding of malicious content.

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_off000027c3.bin
0c3d4071d94636dc645cc18c3978808201dc93084cfed7f5edc06ee53928a39e
rtf-objdata-decoded RTF \objdata at offset 0x27C3 1413 bytes