Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 144606414d0e0759…

MALICIOUS

RTF / .DOC

4.5 KB
MD5: c5d2510bc1d38b70083c71dd58a15ce0 SHA-1: 9a69ec5d4bb35265fa2893b96afb51ca666ad8d0 SHA-256: 144606414d0e0759ec81c3db3e14bd0a25165b766139e13fb230c4610488b02b
180 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1566.001 Spearphishing Attachment

The RTF file contains embedded OLE objects, specifically triggering the CVE-2017-11882 vulnerability through the Equation Editor. This exploit allows for arbitrary code execution, indicating a malicious intent to compromise the user's system. The presence of multiple OLE object-related heuristics strongly supports this attack 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_off0000009f.bin
b583d23167b66f30dcfb87872f986b898e93dc17672e92bfb2dec6488216d341
rtf-objdata-decoded RTF \objdata at offset 0x9F 2071 bytes