Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 b101d52054a46357…

MALICIOUS

RTF / .DOC

40.5 KB First seen: 2023-02-09
MD5: 1938581d6a8014db45518cb12b0f7205 SHA-1: 3a73a6ef8c14e251e7bc21ec8babe4b1460f0ded SHA-256: b101d52054a4635775ed7aecdbc5844fee823783c655e77e96d1a27b70950a45
140 Risk Score

Malware Insights

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

The RTF document contains an embedded OLE object with an Equation Editor ProgID, triggered by \objupdate, which is a known exploit technique. The document body includes a lure instructing the user to 'Enable editing' to view the content, indicating a social engineering attempt to facilitate exploitation.

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_off000045e4.bin
d0ecba282033341e501332bda84070c00431ee7e105da6d3b134fd7e0ed1ea20
rtf-objdata-decoded RTF \objdata at offset 0x45E4 2241 bytes