Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 6aef004bb95e4d3f…

MALICIOUS

RTF / .DOC

24.4 KB
MD5: df7c3db234fc1133486a64b284925889 SHA-1: 0e54afa75062a29e4ecfe880d1fb841d188808c7 SHA-256: 6aef004bb95e4d3f362493cb06a6cbddd1b60bbf1b276865804bf55b90c47e24
180 Risk Score

Malware Insights

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

The RTF file contains an embedded OLE object that exploits the Equation Editor vulnerability (CVE-2017-11882). This exploit is designed to execute arbitrary code, likely as a first stage to download and run a secondary payload. The presence of the `EQuaTion.3` ProgID is a strong indicator of this specific exploit.

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_off0000132a.bin
4502f92938daefa11fd6af5294e5d7404053600aba2caba6f18ccaaa87020694
rtf-objdata-decoded RTF \objdata at offset 0x132A 1958 bytes