Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 b8948e6548c9c766…

MALICIOUS

RTF / .DOC

4.0 KB
MD5: 96665585fc0be1b6d2092e5858c126b6 SHA-1: 766fa4b1381c6a78b994c75e7280ac16f1fb15b3 SHA-256: b8948e6548c9c766d138b93ed76848d815bff04dcaea23a33f936ec614beeccb
120 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution

The RTF document contains embedded OLE objects and specifically triggers the Equation Editor vulnerability. The ".objupdate" directive indicates that the embedded object will be activated automatically upon opening the document, leading to the exploitation of the Equation Editor. This is a common delivery mechanism for malware that aims to execute arbitrary code on the victim's machine.

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_off000000b6.bin
022d2ff0dce3d69af3ad30c3626441c2ede5da3400cca9306f513b54b3097b36
rtf-objdata-decoded RTF \objdata at offset 0xB6 1746 bytes