Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 8e51596bbc772fdf…

MALICIOUS

RTF / .DOC

18.5 KB First seen: 2023-03-13
MD5: 11c3ad999a8cc87c01a7af1f045f97ac SHA-1: d6fc09261673e11b3bb051ac57c8e11b52833a2f SHA-256: 8e51596bbc772fdf8598df6c1dd9619675f53464651a203b4e27542f3d4fc05a
140 Risk Score

Malware Insights

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

The file is an RTF document containing an embedded OLE object, specifically identified as exploiting the Equation Editor vulnerability. The document body provides a lure to encourage users to enable editing, which would likely trigger the OLE object's execution. The presence of \objdata and \objupdate directives further indicates an attempt to activate embedded content.

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_off00002b22.bin
251c141f78c220bca767a3bf39a9090cb148f1fd52d02649dd9283cbb6043fff
rtf-objdata-decoded RTF \objdata at offset 0x2B22 1744 bytes