Malicious RTF — malware analysis report

Static analysis result for SHA-256 798fa6d044ede82b…

MALICIOUS

RTF

40.8 KB First seen: 2023-07-10
MD5: 96908698ef1a19e7b6c4cc2f52637d3b SHA-1: c5e1deb88c686172b30cc21f92747da8d95f7d5b SHA-256: 798fa6d044ede82b78358f22b37053faad937fe49e84a0f98c7bd3f7e329d759
180 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 RTF document contains heuristics indicating the exploitation of Microsoft Equation Editor via an OLE object, a known vulnerability. The document body includes a lure instructing the user to 'Enable editing', which is a common tactic for macro-based malware droppers. The embedded OLE object likely contains a malicious payload designed to be executed upon activation.

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_off0000569d.bin
bf62073bada307c7894f47c15f8e524e105b8065353db20f4991996cfcb8b9ee
rtf-objdata-decoded RTF \objdata at offset 0x569D 1544 bytes