Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 418241e8bbf66d6e…

MALICIOUS

RTF / .DOC

33.7 KB First seen: 2023-05-18
MD5: d45d2fc3e002516560114bc996752ec5 SHA-1: 16ee066cfdd7efa3a9547b2d43349f6b9d4a68a1 SHA-256: 418241e8bbf66d6efc7a37d250e0486544f141ff5405cef887216567164e7d83
140 Risk Score

Malware Insights

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

The RTF document contains an embedded OLE object with an Equation Editor ProgID, triggered by \objupdate, indicating an attempt to exploit a known vulnerability. The document body includes a lure instructing the user to 'Enable editing' to view the content, a common tactic for macro-based or exploit-laden documents. The embedded OLE object is the primary indicator of compromise.

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_off0000433f.bin
7927c8684f8bbfb1ccd2ef7e5276981a9056a721de32c06afdf5d90ca1748aa0
rtf-objdata-decoded RTF \objdata at offset 0x433F 1574 bytes