Malicious RTF — malware analysis report

Static analysis result for SHA-256 f40634df7d95e408…

MALICIOUS

RTF

77.7 KB First seen: 2023-09-20
MD5: 5f794bed7fe4620ecf5f348acb9c126c SHA-1: ab9d0b014eabdfcb46480882bd0390db14d39565 SHA-256: f40634df7d95e40866241f72fc2f1c36cebe90304662b81fa4332b0c19f81f0a
180 Risk Score

Malware Insights

MITRE ATT&CK
T1204 User Execution T1204.002 Malicious File T1566 Phishing T1566.001 Spearphishing Attachment

The RTF file contains OLE object data and specifically triggers heuristics related to Equation Editor exploitation and automatic OLE activation. The document body includes a lure instructing the user to 'Enable editing' to bypass security measures. This indicates the file is designed to exploit vulnerabilities in OLE object handling to execute a 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.
  • Automatically linked OLE object high RTF_OBJAUTLINK
    RTF contains \objautlink — an automatically linked OLE object surface that can be updated or activated when Word opens the document.
  • \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_off000037a9.bin
16b86bbc7ee79403244550831c740d98388697f21f7bdaa645171814c96d8bc7
rtf-objdata-decoded RTF \objdata at offset 0x37A9 1795 bytes