Malicious RTF — malware analysis report

Static analysis result for SHA-256 b966ba8c9a5e820e…

MALICIOUS

RTF

57.0 KB First seen: 2023-09-11
MD5: 0b6d552a2112526089b08ef478a17109 SHA-1: ce4970823850b4dde525492a07d0f4a0768680ca SHA-256: b966ba8c9a5e820e7e5b694e97330c517ff6ab944a4062ab12c55686a4c0930b
180 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious File

The RTF file contains an embedded OLE object with a split Equation Editor ProgID, indicating an attempt to exploit a known vulnerability. The 'SE_ENABLE_LURE' heuristic suggests the document prompts the user to enable editing, which is a common tactic for macro-based malware droppers. The presence of OLE object data and auto-linking further supports the exploitation of embedded objects to achieve code execution.

Heuristics 5

  • 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.
  • Automatically linked OLE object high RTF_OBJAUTLINK
    RTF contains \objautlink — an automatically linked OLE object surface that can be updated or activated when Word opens the document.
  • \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_off0000262e.bin
e8da542fdac53f36045cacbc6e67e081e94ce7ee1da6c6b11118c11456481383
rtf-objdata-decoded RTF \objdata at offset 0x262E 1945 bytes