Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 84dfcfdafb476542…

MALICIOUS

RTF / .DOC

24.2 KB First seen: 2022-11-03
MD5: 6f8a8cc4e391439e5b37ff8eb14bb4b0 SHA-1: 4c5647cc57082cbe7316c84faffd9ef0f75c2489 SHA-256: 84dfcfdafb476542e581bca6f49000a3b868eafb0d9eb475187c061dc615cc79
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 the Equation Editor vulnerability. The \objupdate directive forces OLE activation, and the document body includes a lure instructing the user to 'Enable editing', which is a common technique for malware droppers to bypass macro security settings. The primary goal is to exploit the Equation Editor vulnerability to execute a malicious payload.

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_off00004b46.bin
18a352f2718b835cd128aa27d992f39c2f5e335e671b4a84e003272bab113d93
rtf-objdata-decoded RTF \objdata at offset 0x4B46 1359 bytes