Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 a5d83f25c6751044…

MALICIOUS

RTF / .DOC

93.4 KB First seen: 2023-10-24
MD5: 4e3b9b06dc44119372a0dfc65322496b SHA-1: 25c6730b491be95674ab3150c84068a39937dafc SHA-256: a5d83f25c675104454de24fe6452127f1e655ebb655a3a8fd5a0d4d057007e51
140 Risk Score

Malware Insights

MITRE ATT&CK
T1204.002 Malicious File: User Execution T1059.005 PowerShell

The sample is an RTF document exploiting the Equation Editor vulnerability, indicated by the RTF_EQUATION_EDITOR and RTF_OBJUPDATE heuristics. The SE_ENABLE_LURE heuristic confirms the document contains instructions to enable editing, a common social engineering tactic. The embedded OLE object data suggests it's designed to deliver a secondary 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_off00002faf.bin
ccab3fb59389a366c30a8c13505bfd611360352f173fe9447f68de2892f206d9
rtf-objdata-decoded RTF \objdata at offset 0x2FAF 1947 bytes