Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 66f892880b4dd1f1…

MALICIOUS

RTF / .DOC

19.2 KB
MD5: 583d21008e654e5b6f4860adf74118c6 SHA-1: 387256acf4c3f16cd2f321bc54417b727623b433 SHA-256: 66f892880b4dd1f186df198c4e3fd45d87053628a544db9e24b57b89c40e1d3a
120 Risk Score

Malware Insights

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

The sample is an RTF document containing embedded OLE objects and specifically triggers heuristics for the Equation Editor vulnerability. This indicates exploitation for client execution, likely delivered via spearphishing. The embedded OLE object data is a key indicator of the exploit mechanism.

Heuristics 3

  • 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

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off00000cf0.bin
5c7d339ad249113f6a00dc8d3ee4b3d1be2827ead4e20341357f375e3cfc95e8
rtf-objdata-decoded RTF \objdata at offset 0xCF0 1549 bytes