Malicious RTF — malware analysis report

Static analysis result for SHA-256 97409494aa715ecb…

MALICIOUS

RTF

89.2 KB First seen: 2024-08-29
MD5: fdff090601b2ddef31b254e19bf6cb60 SHA-1: b855f236c953dfc052c487e8566bd113acf2051c SHA-256: 97409494aa715ecb6583f6628e23f9a9e8834a66b167442019418c64a3840b21
160 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1105 Ingress Tool Transfer

The RTF file contains OLE object data and specifically triggers heuristics related to Equation Editor exploitation and automatic OLE activation. This indicates the file is designed to exploit a vulnerability, likely CVE-2017-11882, to achieve code execution. The embedded OLE object, decoded as objdata_00_off00001035.bin, is the likely component that carries out the exploit. The ultimate goal is presumed to be downloading and executing a second-stage 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.
  • 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

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off00001035.bin
11eefcf963598409e92924ecc52c2eea1e2847dee29d55df026bffc6ea9b68f9
rtf-objdata-decoded RTF \objdata at offset 0x1035 1915 bytes