Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 9b8771a438cba87d…

MALICIOUS

RTF / .DOC

39.4 KB First seen: 2023-02-13
MD5: 7d8ffb273bc7812cc53d575891e9a7b8 SHA-1: d63fa2c44506c4fcb650fe5b05dd7e26e21d6784 SHA-256: 9b8771a438cba87dfb6e5edafd442fba674345f2a2fc84dcfc542d15c39a3b32
140 Risk Score

Malware Insights

MITRE ATT&CK
T1204 User Execution: Malicious Link T1059 Command and Scripting Interpreter

The RTF document contains an embedded OLE object with a split Equation Editor ProgID, a known exploit technique. The \objupdate directive forces OLE activation, and the document body includes a lure to 'Enable editing'. This combination strongly suggests an attempt to exploit a vulnerability, likely CVE-2017-11882, to execute a malicious payload.

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_off00004fa1.bin
1a8ab58f58946b099065fbde2c22458af89d9dece8a2b43c75a5d42cbd25cdd8
rtf-objdata-decoded RTF \objdata at offset 0x4FA1 1702 bytes