Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 bd532d8ac0c16ac4…

MALICIOUS

RTF / .DOC

17.5 KB
MD5: 7bb060c5854b2d98b74402cf9720d4ce SHA-1: 16af0fd7c6ea92758aedd8ecd63d8e192ca278e0 SHA-256: bd532d8ac0c16ac4fa4f81ab2f4b9937606c9f6ed6b6268ea1e4714e9210157b
180 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, specifically triggering the CVE-2017-11882 vulnerability related to Equation Editor. This indicates an attempt to execute arbitrary code by exploiting a known Microsoft Office vulnerability. No document body or script content was available for further analysis, but the heuristic firings strongly suggest exploitation.

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_off00000f32.bin
632547338dee7bfef8ae3e9b8b0791c63215b24ac0d1e4b95c6daa12f8f736ff
rtf-objdata-decoded RTF \objdata at offset 0xF32 1828 bytes