Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 70f841604648c61a…

MALICIOUS

RTF / .DOC

3.7 KB
MD5: 2c076766a35b1a97015370e8fee3026f SHA-1: c83554fec8567876e70445221141076663d4d507 SHA-256: 70f841604648c61ae31b68700b0b718414213ee8911324dea908d8001a805909
180 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1566.001 Spearphishing Attachment

The RTF document contains embedded OLE object data, specifically triggering the Equation Editor vulnerability CVE-2017-11882. This exploit is designed to execute arbitrary code, likely leading to the download and execution of a secondary malicious payload. The presence of ".objupdate" further indicates an attempt to force OLE object activation.

Heuristics 5

  • Equation Editor activation — CVE-2017-11882 related high CVE related CVE_2017_11882_ACTIVATION_RELATED
    RTF decodes to an Equation.3 ProgID and requests OLE activation with \objemb plus \objupdate. This reaches the legacy Equation Editor attack surface used by CVE-2017-11882/CVE-2018-0802 documents, but the malformed MTEF/native payload needed for stronger attribution was not recovered.
  • 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 2 \objdata section(s) — embedded OLE objects
  • Embedded OLE object medium RTF_OBJEMB
    RTF contains \objemb — embedded OLE object

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off0000009a.bin
49a65e1a0d3143d3afcaea18db68f1821bae9aba816571c54f16106df34f7da5
rtf-objdata-decoded RTF \objdata at offset 0x9A 1659 bytes