Malicious RTF — malware analysis report

Static analysis result for SHA-256 155b83a9ec6ea8e3…

MALICIOUS

RTF

1.10 MB
MD5: 675b95f2672719792ef191876f42690f SHA-1: 09498027efa0a64e0e8e2928159073b432b03f4a SHA-256: 155b83a9ec6ea8e37ddd8efc010a9b024c86d7dea3f8c55807f808c64e422fcb
180 Risk Score

Malware Insights

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

The RTF document contains embedded OLE objects, specifically identified as related to Equation Editor and CVE-2017-11882. The presence of \objupdate and the decoded object data strongly indicate an attempt to exploit this known vulnerability for client-side execution. The document body content appears to be obfuscated script fragments, further supporting the malicious intent.

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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off000011e1.bin
773ef1bd1f6073e647495046dd53c0a6428412122263783b93a8090356814311		 rtf-objdata-decoded RTF \objdata at offset 0x11E1 35440 bytes
objdata_01_off00021bf7.bin
a6f253d6bbd0460ac77e10ef1bc8f05800fa5562b3652b8ea10ed15d9e3c5eda		 rtf-objdata-decoded RTF \objdata at offset 0x21BF7 246442 bytes

Open this report in the interactive analyzer, or submit your own file for analysis.