Malicious RTF — malware analysis report

Static analysis result for SHA-256 7962acb951893a7f…

MALICIOUS

RTF

37.0 KB First seen: 2023-07-04
MD5: f0a7729bda6a95e7a0d9c1b6804e7e9f SHA-1: aed6edb5380af3864621231846548bf2bb6c0762 SHA-256: 7962acb951893a7f53511cba33f4cca6d8fa3da3a7e7a622d148827687327dca
180 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 User Execution: Malicious File

The RTF document contains an OLE object with a split Equation Editor ProgID and is configured to automatically update, indicating an attempt to exploit a known vulnerability. The presence of the SE_ENABLE_LURE heuristic suggests the document also contains text prompting the user to enable editing or macros, a common social engineering tactic to bypass security measures. The primary goal is likely to leverage the exploit to download and execute a secondary payload.

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_off00004a80.bin
233d6529126c23dc92678736c6951e008bcbfbb304818400136806891c445516
rtf-objdata-decoded RTF \objdata at offset 0x4A80 1946 bytes