Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 9ca15a88bcffa7a3…

MALICIOUS

RTF / .DOC

105.5 KB First seen: 2023-09-29
MD5: aee4edb54123e693d8d5ab04fda43411 SHA-1: 59c61b863cef3f5d270db3a9ca5d67acbc2a85a3 SHA-256: 9ca15a88bcffa7a3aaf699b6b00fee7d3c0221745b8200ae00a4b1bc76afcedc
140 Risk Score

Malware Insights

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

The RTF document contains an embedded OLE object with a specific Equation Editor ProgID, triggered by an \objupdate directive. This strongly suggests an attempt to exploit the Equation Editor vulnerability (CVE-2017-11882). The document body includes a lure instructing the user to 'Enable editing', which is a common tactic for macro-based or exploit-laden documents to bypass security warnings.

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_off00006899.bin
5c7b05b27e1e2ec813845316b187fd19a91f523f10e54efb0b9f91f024f2e06d
rtf-objdata-decoded RTF \objdata at offset 0x6899 1999 bytes