Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 fb3221e17abe8fac…

MALICIOUS

RTF / .DOC

52.8 KB First seen: 2023-10-02
MD5: 4693b7ba6d5e31918330284d71f818f3 SHA-1: 6e0debfe33f47802307aa046f44dc43629b33df6 SHA-256: fb3221e17abe8facb098a47f9fa8ff242a67b63a01ac7c97525ff8f266fb9ac6
160 Risk Score

Malware Insights

MITRE ATT&CK
T1204 User Execution: Malicious Link T1059 Command and Scripting Interpreter

The RTF document contains an embedded OLE object, specifically identified as an Equation Editor exploit. The document body includes a lure instructing the user to 'click Enable editing from the yellow bar above', which is a common tactic to bypass security measures and execute embedded malicious content. The presence of the Equation Editor exploit strongly suggests an attempt to leverage CVE-2017-11882 for arbitrary code execution.

Heuristics 5

  • 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
  • Embedded OLE object medium RTF_OBJEMB
    RTF contains \objemb — embedded OLE object
  • 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_off00002c2e.bin
6ccf9c65702f97146cff3c61ac20c99057d15c50f34265ed6f58b828cd12b121
rtf-objdata-decoded RTF \objdata at offset 0x2C2E 1751 bytes