Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 6e357d913c3acdd4…

MALICIOUS

RTF / .DOC

1.81 MB
MD5: 6309933eb67b93ede338823f5b4c9ba4 SHA-1: 333957590cab46884be7b7f8b1b6f501f3e1c61c SHA-256: 6e357d913c3acdd44e402b9b9ee5f83196b6847a64f41ccd7846eccb9d721159
220 Risk Score

Malware Insights

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

The RTF document contains OLE object data and specifically triggers heuristics related to CVE-2017-11882, indicating the exploitation of a vulnerability in the Equation Editor. This exploit is designed to execute a second-stage payload, likely a binary, leveraging the embedded OLE object.

Heuristics 5

  • Equation Editor OLE1 native payload — CVE-2017-11882 related critical CVE related CVE_2017_11882_RELATED
    RTF decodes to an OLE1 Equation.3 embedded object whose native data is large and payload-like, and \objupdate requests automatic activation. This is the delivery shape used by Equation Editor RCE documents such as CVE-2017-11882/CVE-2018-0802, but the malformed MTEF record needed for exact 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.
  • Large hex data blocks in OLE object high RTF_EXCESSIVE_HEX
    RTF contains ~1894KB of hex-encoded data inside \objdata sections — may hide a payload
  • 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_off0000008a.bin
7293462ecbabe34d405260cca2e9bf858cc95cdd790a07a2c791f4a6dbfd241d
rtf-objdata-decoded RTF \objdata at offset 0x8A 947223 bytes