Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 e052206ce8d4fc11…

MALICIOUS

RTF / .DOC

34.1 KB First seen: 2023-04-24
MD5: d8f752aa33c54bc076295cc4917e5b6c SHA-1: a031400dcd64829a1486c2806c266e94432cce01 SHA-256: e052206ce8d4fc1107000f06a8267d47f44cdabb3207b5adfc5626e0150d8dda
140 Risk Score

Malware Insights

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

The file is an RTF document containing an embedded OLE object, specifically identified as an Equation Editor exploit. The presence of \objupdate indicates that the object is designed to activate automatically upon opening or when the user enables editing, as suggested by the SE_ENABLE_LURE heuristic. This strongly points to a classic exploit delivery mechanism.

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_off00001ea6.bin
a7d08d76b913b05592f724b5b99a376739b019955944a3a37e293c6f7457f1c6
rtf-objdata-decoded RTF \objdata at offset 0x1EA6 2071 bytes