Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 32907a59dbe33c5a…

MALICIOUS

RTF / .DOC

34.5 KB First seen: 2022-12-09
MD5: 44c5ed7722cb4e5417e94bfc832d2625 SHA-1: b71c9f211fa42adba284dd209554645ef936d1cf SHA-256: 32907a59dbe33c5ae77318b09a17531a3164b619d067aab7a5ca09acfa5c30c1
140 Risk Score

Malware Insights

MITRE ATT&CK
T1204 User Execution T1059.005 PowerShell

The sample is an RTF document that leverages an Equation Editor vulnerability, indicated by the RTF_EQUATION_EDITOR and RTF_OBJDATA heuristics. The SE_ENABLE_LURE heuristic confirms the presence of a social engineering tactic to trick the user into enabling content. The RTF_OBJUPDATE heuristic suggests that the embedded OLE object is designed to be activated automatically upon opening, likely to trigger the exploit.

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_off000059c7.bin
6f34d531ce61b06fc58b3571397cbdf341d4820e00722a92f3b7c82001328e2b
rtf-objdata-decoded RTF \objdata at offset 0x59C7 1849 bytes