Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 d9031317ccbbce3f…

MALICIOUS

RTF / .DOC

29.6 KB First seen: 2023-02-23
MD5: d9d58d3a5ac25de8bdd3d84524190284 SHA-1: b50ed5bda4f9edf0c681d9a14031a11e2b1a6b16 SHA-256: d9031317ccbbce3f1d361d1569a44d7001ed7fba70c78321be147cfbd3edfb14
140 Risk Score

Malware Insights

MITRE ATT&CK
T1204 Malicious Link T1204.002 Malicious Link: Malicious File T1059 Command and Scripting Interpreter T1059.005 Command and Scripting Interpreter: Visual Basic

The RTF document contains an embedded OLE object with a split Equation Editor ProgID, indicating an attempt to exploit a known vulnerability. The \objupdate directive forces OLE activation, and the document body includes a lure to 'Enable editing', common for macro-based malware droppers. The exploit likely leads to the execution of a secondary payload, though no scripts were directly extracted.

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_off0000277f.bin
632ed465f8f913b324be83bf74473dad9e9eb98d9ab6d7912a8dba258e3758c0
rtf-objdata-decoded RTF \objdata at offset 0x277F 1571 bytes