Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 00bf53b450bc1b30…

MALICIOUS

RTF / .DOC

69.4 KB
MD5: 0673492f28ab092e101efc7d30083752 SHA-1: a08fa24e5eafff3f48dc2e5ce13221177d490965 SHA-256: 00bf53b450bc1b307438aef45f542c370d2d396805c52139721a6257fefb5a43
180 Risk Score

Malware Insights

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

The RTF document contains embedded OLE objects, specifically triggering the CVE-2017-11882 vulnerability related to Equation Editor. This exploit allows for the execution of arbitrary code, likely to download and run a secondary payload. The presence of RTF_OBJDATA, RTF_OBJEMB, RTF_EQUATION_EDITOR, and RTF_OBJUPDATE heuristics strongly indicates this exploitation vector.

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_off00001c71.bin
37e5aa4e2319a1b23704e13fed90d37477ca9577ef1e6b66e30a09a93f72ec19
rtf-objdata-decoded RTF \objdata at offset 0x1C71 2076 bytes