Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 461b4bbefc9a6dba…

MALICIOUS

RTF / .DOC

26.6 KB
MD5: a0cdec4ff5b7b9e5f70b11b934e4754f SHA-1: cd097cddf477382edb9bbb0300074280ea35f46f SHA-256: 461b4bbefc9a6dbacbf9b569acdc22af5cae7d70d902d3cc4239c8be18413dbd
120 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1059.001 PowerShell

The sample is an RTF document that contains OLE object data and triggers an objupdate event, indicating it's designed to activate embedded objects. The critical heuristic RTF_EQUATION_EDITOR specifically points to a known vulnerability in the Equation Editor component, which is commonly exploited to achieve arbitrary code execution. This technique is likely used to download and execute a second-stage payload.

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_off00002058.bin
f213e80a8f421691b27b3a508de4ab833b422dfa0a20be1fd4c7b1d48f5c1d8c
rtf-objdata-decoded RTF \objdata at offset 0x2058 1695 bytes