Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 2cd0c2ff7b9c54ee…

MALICIOUS

RTF / .DOC

12.8 KB First seen: 2023-06-01
MD5: f775d1b3af28d354187521fa070493c9 SHA-1: 3aeb1fdce7d3e84097e703a22ff1e7c73243f756 SHA-256: 2cd0c2ff7b9c54ee4a4268bd9924d2415022c23d7022a7cbe065e347bcb833d4
120 Risk Score

Malware Insights

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

The sample is an RTF document that contains OLE object data and specifically triggers the RTF_EQUATION_EDITOR heuristic. This indicates the exploitation of a vulnerability within the Equation Editor component, likely to achieve code execution. The RTF_OBJUPDATE heuristic further suggests that the embedded object is designed to be automatically activated, leading to the execution of a secondary payload. The document body is unreadable, but the heuristics strongly point to a classic exploit delivery mechanism.

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 1 \objdata section(s) — embedded OLE objects

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off0000078f.bin
41db880c007aceab060ad03b27a4282cf7353ae1f3f4fb5883765fc8762e0504
rtf-objdata-decoded RTF \objdata at offset 0x78F 1399 bytes