Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 2892f4dac09f00ae…

MALICIOUS

RTF / .DOC

35.3 KB First seen: 2023-02-16
MD5: 8ca504c8436e4808e80f80e496c29aef SHA-1: f0d3c80605abc4c8c6227b6780e1ed41cafcecc5 SHA-256: 2892f4dac09f00aec17e23f6ee7a629dea9729fa392b985bbb1f8e5d434e689a
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 RTF document contains an embedded OLE object and uses an \objupdate directive, indicating an attempt to exploit a vulnerability. The critical RTF_EQUATION_EDITOR heuristic strongly suggests a known exploit targeting Microsoft Equation Editor. The document body includes a lure instructing the user to 'Enable editing', a common tactic to bypass security measures and trigger the exploit.

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_off00004846.bin
2982545df6447d24df75875f9b746555c21e5c8c0496e5aa5413f668da9204cc
rtf-objdata-decoded RTF \objdata at offset 0x4846 1472 bytes