Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 894c98ddcd0a6c74…

MALICIOUS

RTF / .DOC

3.9 KB
MD5: 978b040be4292e7eb99e70432a133f50 SHA-1: 1719746030549b38d536e05da7b919efe3eeebea SHA-256: 894c98ddcd0a6c743512480c44002a53554186c7f06c5f122878977a74b8cb70
120 Risk Score

Malware Insights

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

The RTF document contains embedded OLE objects and specifically triggers the Equation Editor vulnerability. The ".objupdate" directive forces the activation of this embedded object, leading to the exploitation of the Equation Editor to execute arbitrary code. This is a common technique for delivering malicious payloads.

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_off0000007a.bin
6fd34662b89736c8897d442948c950c76bf2192786a3a981d4aa7c224b65080c
rtf-objdata-decoded RTF \objdata at offset 0x7A 1775 bytes