Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 a3a8df4eaad6b20c…

MALICIOUS

RTF / .DOC

4.0 KB
MD5: 59d554039c9b99bf03face78299b94b9 SHA-1: 1d5384684489b69721ec4a41e55e02548e9f6aa3 SHA-256: a3a8df4eaad6b20c87a7aa91eb008f3a49945e3893078fd361ce47fce303429a
120 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution

The RTF document contains embedded OLE object data, specifically triggering the Equation Editor vulnerability. The ".objupdate" directive indicates that the embedded object is intended to be activated automatically upon opening the document, leading to the execution of arbitrary code. This is a common delivery mechanism for exploiting older Microsoft Office vulnerabilities.

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_off000000cb.bin
0a5e67ab8c77dc212b34e4f2e2e0737008721f675c4169028cba8d67dbf14b4a
rtf-objdata-decoded RTF \objdata at offset 0xCB 1782 bytes