Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 d2f9099d51c6d029…

MALICIOUS

RTF / .DOC

18.7 KB First seen: 2022-10-06
MD5: 17900788a05c570b0f041d1cdecf303e SHA-1: 33d0d82ccf6d16e37ef2c4b78a00f82ed283d28b SHA-256: d2f9099d51c6d02926f1d5dc98b4210c12af2920736db30bf63aab70423329dd
140 Risk Score

Malware Insights

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

The RTF document contains an embedded OLE object with an Equation Editor ProgID, and uses \objupdate to force activation. The document body includes a lure instructing the user to 'Enable editing', a common tactic for macro-based malware droppers. The presence of these indicators suggests the file is designed to exploit user interaction to execute malicious code.

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_off00001a81.bin
b84e6d9baca7cad2f708a9258d55712a2b3e2468f596dcdfd22ea4abb032d09a
rtf-objdata-decoded RTF \objdata at offset 0x1A81 1774 bytes