Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 8eb440576697d1db…

MALICIOUS

RTF / .DOC

53.4 KB
MD5: decb54a62019ead00e1ad6fbeadd793f SHA-1: b82c2e03ef1ceb732447f5ebd798dfb9e978d643 SHA-256: 8eb440576697d1dbe751598042584b77b4f7443cd4a0b09d8964710ac7d38234
180 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1559.001 Component Object Model

The RTF file contains multiple indicators of exploitation, specifically related to CVE-2017-11882. The presence of OLE objects and Equation Editor-related heuristics strongly suggests that the file is designed to trigger this known vulnerability. The ".objupdate" directive further indicates an attempt to force OLE object activation, leading to arbitrary code execution.

Heuristics 5

  • Equation Editor activation — CVE-2017-11882 related high CVE related CVE_2017_11882_ACTIVATION_RELATED
    RTF decodes to an Equation.3 ProgID and requests OLE activation with \objemb plus \objupdate. This reaches the legacy Equation Editor attack surface used by CVE-2017-11882/CVE-2018-0802 documents, but the malformed MTEF/native payload needed for stronger attribution was not recovered.
  • 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
  • Embedded OLE object medium RTF_OBJEMB
    RTF contains \objemb — embedded OLE object

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off00000626.bin
a8de442b76a5ab96ce13bf8c5432d31fd4ee634980dbc019464e1d5d86fc9c2b
rtf-objdata-decoded RTF \objdata at offset 0x626 1851 bytes