Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 2e3ba367f7f30245…

MALICIOUS

RTF / .DOC

48.9 KB
MD5: c59196fd8fa1389a3257937db3ea6269 SHA-1: 3a2597fd5fa22c4387c0c0166042b4b23ca11c53 SHA-256: 2e3ba367f7f302454b4de5bf5b58ba591b372f696231a0dc892b577270fcd1c3
120 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1059.001 PowerShell

The sample is an RTF document that leverages the Equation Editor vulnerability, as indicated by the RTF_EQUATION_EDITOR and RTF_OBJDATA heuristics. The RTF_OBJUPDATE heuristic suggests that the embedded OLE object is automatically activated. The primary attack vector appears to be exploitation of the Equation Editor component to achieve code execution, likely for downloading and executing a subsequent stage.

Heuristics 3

  • 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 2 \objdata section(s) — embedded OLE objects

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off000015d1.bin
df489510800de99ab08cd9d2fd61bcdf98e2e11a1322ac1a357881e890491b5c
rtf-objdata-decoded RTF \objdata at offset 0x15D1 1903 bytes