Malicious RTF — malware analysis report

Static analysis result for SHA-256 47811af505eb2a00…

MALICIOUS

RTF

42.2 KB First seen: 2023-07-18
MD5: 216174f069f376a3173e920b32543d87 SHA-1: 6c7b0e096a63e30fef0a7ca79da52e9d7f2e9b7a SHA-256: 47811af505eb2a00016a2c9e5507ee4e8b99f5d756304582bd7ed5733f8404ef
160 Risk Score

Malware Insights

MITRE ATT&CK
T1204 User Execution: Malicious Link T1566.001 Phishing: Spearphishing Attachment T1059.005 Command and Scripting Interpreter: Visual Basic

The RTF file contains an embedded OLE object, specifically identified as an Equation Editor exploit. The document body includes a lure instructing the user to 'Enable editing' to view the content, which is a common tactic for macro-based malware. The presence of ".objupdate" further indicates an attempt to force OLE activation, likely to trigger the exploit and download a secondary payload.

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_off0000422d.bin
cf113ef17a05977ad50c37fbd4bd98d414fad541c57c1c7c0c36e511216f86bb
rtf-objdata-decoded RTF \objdata at offset 0x422D 1977 bytes