Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 60f4e05710213731…

MALICIOUS

RTF / .DOC

12.0 KB First seen: 2022-03-01
MD5: 8426095f758e30898cfab26e75684079 SHA-1: b4aa2256a91b2ac7e9e32c4a4d8b8cd38f5b11d0 SHA-256: 60f4e05710213731a1f92cf6c48a3818eb7c9ecf3f0236f4034994ad0a953079
120 Risk Score

Malware Insights

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

The RTF document contains embedded OLE object data and specifically triggers the Equation Editor vulnerability. The presence of \objupdate indicates an attempt to force OLE activation, which is a common method for exploiting this vulnerability to achieve code execution. The extracted objdata artifact is likely the payload or a component thereof.

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_off0000207f.bin
d47c9c4970730d2e610842dd390bb802c9dbe0e35e644ba83a63954324a2d045
rtf-objdata-decoded RTF \objdata at offset 0x207F 1822 bytes